Government & Advisory Services
Strategic property advice for local, regional, and national government agencies.
Make critical decisions that contribute to the success of your investments and your organisation with our leading government property advisory services. Whether you’re a local, regional or national government agency– we have the expertise and technology to ensure high-quality advice and reports to empower more informed property decisions.

Our Coverage
We have a specialised team of professional valuers who handle government property services with unmatched knowledge and expertise to support your property decisions.

Our Technology
Our technology enhances the valuation process for everyone involved with customisable, automated workflows and centralised systems to access, manage, and deliver your reports.

Our Process
Opteon works with a vast range of Central, Regional & Local Government departments & their agencies.
Government Advisory Services
We provide a range of property advisory services with individualised solutions and expertise. Our advisors are skilled at analysing the local property markets, understanding various market sectors – from residential to rural –, and providing strategic property and risk management advice for a range of government departments and agencies.
Rating Valuations
We are proud to be the Valuation Service Providers (VSP) for several Councils in New Zealand, providing our customers with market-leading valuation management platforms to enable business decisions through the utilisation of technology.
Financial Reporting for Local Governments
Make critical decisions that contribute to the success of your investments and your organisation with our leading government property advisory services.
Rating Valuations
We are proud to be the Valuation Service Providers (VSP) for several Councils in New Zealand, providing our customers with market-leading valuation management platforms to enable business decisions through the utilisation of technology.
Financial Reporting for Local Governments
Make critical decisions that contribute to the success of your investments and your organisation with our leading government property advisory services.
Get In Touch with an Expert

Avella Taylor
Director Operations NZ

Chloe Woollard
Government & Advisory Director

Joe Holmes
Associate Director

Anna Watson
Lead Valuer

Ben Roberts
Registered Valuer

Ben Rowsell
Valuer

Ben Williams
Valuer

Clinton Jarman
Registered Valuer

Ewen Lilburn
Appointee Valuer

James Tolich
Associate Valuer

Kathy Zhu
Associate Valuer

Lionel Musson
Registered Valuer

Mark Grinlinton
Registered Valuer

Martyn Oostveen
Senior Rural Valuer

Simon Bryant
Registered Property Valuer

Tahlee Lane
Valuations Manager

Tom Mabbott
Managing Valuer

Angus Walkinshaw
Graduate Valuer

Cameron Dixon
Graduate Valuer

Connor Lyons
Graduate Valuer

Grace Hing
Graduate Valuer

Hayden Loughnan
Graduate Valuer

Shannon Aislabie
Graduate Valuer

Avella Taylor
Formal Qualifications
- Registered Valuer in New Zealand (Member No. NZIV 3780)
- Member of the Property Institute New Zealand
- Property Institute of New Zealand Branch Committee Chair – Auckland
- Bachelor of Commerce (Property Valuation) - Curtin University of Technology Western Australia 2014
Industry Experience
Avella has several years’ experience as a valuer and has been employed by Opteon since 2013. She is the Regional Director of Government Services for New Zealand and leads the Government Department which undertakes valuations throughout New Zealand.
Areas of Expertise
- Valuations for mortgage purposes
- Residential valuations
- Asset valuations for financial reporting and insurance purposes
- Project management and delivery

Chloe Woollard
Formal Qualifications
- Member of the Property Institute New Zealand
- Bachelor of Business – Major in Valuation &
Property Management
Industry Experience
Chloe has been working at Opteon since 2023. She is responsible for overseeing the delivery of Rating Valuations in the Government services team. Chloe has experience in the procurement of Valuation services contracts and managing large scale projects. In addition to her role at Opteon, Chloe also holds board positions in the not-for-profit industry.
Areas of Expertise
- Rating Valuations (maintenance, revaluations & objections)
- Procurement
- Project Management
- Process Improvement

Joe Holmes
Formal Qualifications
- Certified Practising Valuer
- Associate Member of the Australian Property Institute (API Member No. 82770)
- Registered Valuer (NZIV, MPINZ) (Registration Certificate No. 3942)
- Land Valuers Licence (Western Australia) (Licence No. LV45100)
- Bachelor of Applied Science (Property and Valuation) (1st Class Honours)
Industry Experience
Joe is an experienced rating and taxing valuer having commenced his career in Melbourne undertaking a range of valuations for municipalities including Manningham City Council, Kingston City Council, Glen Eira City Council, Frankston City Council, Yarra City Council, Moreland City Council, Mornington Shire and more. He has vast experience returning annual general revaluations, objections, supplementary valuations, public open space contribution valuations, asset valuations, rental determinations and insurance valuations covering a range of property types such as commercial, industrial, residential, and specialist. In 2020 he migrated home to Auckland (New Zealand) and in 2021 joined Opteon as an Associate Director in their Government and Advisory team. He is a Registered Valuer in New Zealand, Certified Practising Valuer in Victoria, and holds a Land Valuers Licence in Western Australia.
Areas of Expertise
- Valuations for property taxation, legislation and policy purposes
- Mass valuation modelling
- Rating and taxing valuations
- Rating and Land Tax objections
- Asset valuations for financial reporting purposes
- Public open space contribution valuations

Anna Watson
Formal Qualifications
- Associate Member New Zealand Institute of Valuers (ANZIV)
- Member of the Property Institute of New Zealand (MPINZ)
- Registered Valuer
- Bachelor of Property Administration (BPA)
Industry Experience
Anna has been working with Opteon since October 2023 in the Government Services team. Prior to joining Opteon, Anna worked as the Lead Residential Valuer at Auckland Council, the largest Territorial Authority in Australasia.
Anna is considered a rating valuations expert with over 25 years’ experience in this field. She specialises in computer assisted mass appraisal utilising the modelled approach to valuation. She has a wide knowledge of the entire valuation process and has had a key role in overseeing and implementing of mass valuations.
Areas of Expertise
- Residential property valuations
- Mass Valuation modelling for revaluations
- Legislation, requirements and procedures for rating valuations
- Procedural and reporting for Land Valuation Tribunal

Ben Roberts
Formal Qualifications
- Bachelor of Business, Majoring in Valuation & Property Management - Massey University
- Registered Valuer - 2023
- Member of the Property Institute of New Zealand (MPINZ)
Industry Experience
Ben started with Opteon in 2019 upon completing his Property degree at Massey University and went on to gain registration as a valuer in 2023. Ben works with the NZ Commercial & Industrial team specialising in a broad range of valuations within Auckland.
Areas of Expertise
- Commercial & industrial valuations
- Pre-sale and pre-purchase advice
- Rental assessments
- Insurance valuations
- Tax depreciation valuations
- Asset valuations for financial reporting purposes

Ben Williams
Formal Qualifications
- BProp (UoA)
Industry Experience
Ben has been with Opteon for eight months after completing his Bachelor of Property with the University of Auckland in 2022. He has assisted in the successful completion of roll maintenance deadlines having gained experience in residential, rural and lifestyle valuations.
Areas of Expertise
Throughout Ben’s time with Opteon, he has been building his expertise in residential and lifestyle valuations.

Ewen Lilburn
Formal Qualifications
- New Zealand Certificate in Engineering
- Bachelor of Business Studies (Massey University - ongoing)
Industry Experience
Ewen has over 15 years’ experience in the property valuation industry, primarily with Government services throughout the Northland region. He is proficient in residential, lifestyle and rural valuation techniques required in the maintenance of the District Valuation Roll and has an in depth knowledge of legislation that impacts rating valuation methodology.
Ewen provides specialist expertise in index creation and statistical interpretation of mass appraised data gleaned from the successful implementation of fourteen district revaluation projects. Ewen’s engineering background brings to Opteon added knowledge of data integrity techniques and the ability to streamline workflow processes for accurate outcomes.
Areas of Expertise
- Residential and lifestyle property valuations
- District Revaluations
- Mass valuation modelling
- Territorial Authority account management
- Asset valuation for private and government clients

Kathy Zhu
Areas of Expertise
- Residential valuations
- Rating valuations
Industry Experience
Kathy began her valuation career in 2019 and joined Opteon in 2023. The majority of Kathy’s expertise is in residential valuations, particularly in rating valuation. She has successfully assisted in completing revaluations and meeting roll maintenance deadlines.
Formal Qualifications
- Registered Valuer
- Member of the Property Institute of New Zealand
- Bachelor of Property – University of Auckland (2018)

Lionel Musson
Formal Qualifications
- Member of Property Institute of New Zealand (Membership No. 7371)
- Registered Valuer in New Zealand NZIV No. 4001; Practising Certificate No. 885
- BBS Property Certificate of proficiency - Massey University New Zealand
- National Diploma Real Estate – University of South Africa
- National Diploma Architecture – Tshwane University of Technology SA
- B.Com Risk Management Certificate - University of South Africa
Industry Experience
Lionel has been working at Opteon for 6 months in the Government Services sector and prior, had worked for a prominent Auckland based Engineering firm for five years as a specialist assets valuer. He is considered to be proficient in the New Zealand financial reporting and insurance valuation field across the North and South Islands with experience in managing larger asset portfolio valuation for local authorities, government institutions, Crown entities and a wide spectrum of private and public organisations.
Lionel is also experienced in condition assessments, asset lifecycle costings, maintenance, and renewal forecasting through reactive and preventative maintenance of assets. Lionel was part of the winning team for the RICS Valuation team for 2020 and 2021.
Areas of Expertise
- Commercial property valuations
- Specialist residential valuations
- Valuation for financial reporting and insurance valuations (PBE IPSAS 16 and PBE IPSAS 17)
- Job management of large-scale asset valuation portfolios
- Property market analysis and reporting.
- Liaise with clients and Auditors

Mark Grinlinton
Formal Qualifications
- B Com Ag (Valuation & Farm Management), 1984.
- Registered Valuer, 1987.
- Associate status of the New Zealand Institute of Valuers, 1989.
- Senior member of the Property Institute of New Zealand, 2005.
Industry Experience
Mark has been responsible for the delivery of over 30 revaluations since 1999 and held leading valuation positions with Valuation NZ, QV, Landmass and Opteon. He began his valuation career in 1984 in the Gisborne office of Valuation NZ. In 1989 he moved to Tauranga and held the position of Rating Valuation Manager for Quotable Value from 1999 to 2004. From 2004 to 2015 he was a director and shareholder of Landmass Technology, until its purchase by Opteon where he held the positions of General Manager Government Services and Rural Director until early 2019. Following a brief absence, he has returned to add his significant experience and assist Opteon in his role as Registered Property Valuer.
Mark has been a Registered Valuer specialising in the delivery of rating valuations for most of his 40-year career. This experience has led to a strong understanding and long involvement in the Rating Valuation industry
Areas of Expertise
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Specialist in all aspects of rural valuations.
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Management roles extending two decades in the successful delivery of Rating Valuation Service Provider contracts.
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Strong understanding of the Rating Valuations Act 1988, associated Rules, the Te Ture Whenua Act 1993 and relevant case law.
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Comprehensive knowledge of the Land Information New Zealand audit requirements.
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Expert witness for Councils on many Land Valuation Tribunal hearings, including cases of national importance involving Maori land and forestry.
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Member of the expert committee that reviewed the 2008 Rating Valuation Rules.

Martyn Oostveen
Formal Qualifications
- Bachelor of Commerce (Agriculture) Majoring in Rural Valuation and Farm Management from Lincoln University.
- Full Member of Property Institute (MPINZ)
Industry Experience
Martyn is an experienced rating valuer and has been with Opteon for over 8 years and during this time has participated and managed several revaluations. His experience extends to dairy, pastoral, lifestyle and residential valuations. Martyn prides himself in his knowledge in rating valuation legislation and the quality assurance of valuations and data. Martyn is working towards becoming a Registered Valuer.
Before entering the property valuation industry, Martyn worked on a dairy farm employed as a manager.
Areas of Expertise
- Rural valuation
- Mass Ad hoc modelling within Valor database
- Mass indexing
- Rating legislation
- Management of valuers and rating staff
- Revaluation and maintenance audits
- General technology
- District valuation roll computer systems

Simon Bryant
Formal Qualifications
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Registered Valuer (Registration Certificate Number: 3751)
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Member of the Property Institute of New Zealand
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Member of the New Zealand Institute of Values (NZIV)
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Bachelor of Business Studies (Valuation and Property Management) – Massey University (Palmerston North)
Industry Experience
Simon has been working with Opteon since 2023, working within the Government Services team as a lead Residential Valuer, contributing the delivery of Rating Valuation contracts in the Wider Auckland and Waikato Regions. Prior to this, he worked as a Valuation Panel Manger, with a focus on Quality Assurance for reporting standards across New Zealand and Relationship Management, with not only valuation firms, but banking clientele. During this time, he obtained extensive knowledge of the International Valuation Standards, Guidance Papers for Valuers and Property Professionals and the Residential Valuation Standing Instructions. He obtained his Registered Valuers Qualification in 2016.
Simon’s specialisation is Residential Valuations, which includes (but not limited to) valuations for Rating and Taxation/Government Services work and valuations for Mortgage Finance Purposes.
Areas of Expertise
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Residential Valuations
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Rating Valuations utilising mass appraisal methodologies
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Rating Valuation Objections
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Valuations for Mortgage Finance Purposes
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Valuations pre purchase/pre-sale advice

Tahlee Lane
Formal Qualifications
- Bachelor of Property
- Certificate III Business Administration
- Entry certification in Business Analysis (ECBA) (In progress)
Industry Experience
Tahlee has been working with Opteon for over 9 years across a number of different departments in both Australia (VIC & NSW) and New Zealand. Previously a Business Analyst in the Cubetec team, she is considered a subject matter expert for the valuation management system Valor, working closely with clients and stakeholders to understand and define product positioning, functional specifications and user requirements and processes.
Tahlee provides broad knowledge on rating and taxing valuation processes and is skilled in effective and supportive client management. She specialises in mass valuation modelling and process improvement by leveraging the use of technology.
Areas of Expertise
- Client & Stakeholder Management
- Mass Valuation Modelling
- Rating and Taxing Valuations
- Valuation Management Systems Expert
- Process Review and Change Management

Tom Mabbott
Formal Qualifications
- Registered Valuer in NZ (Member No. NZIV 4017)
- Member of the Property Institute New Zealand
- Bachelor of Property (BProp) - University of Auckland (2018)
Industry Experience
Tom has built a diverse skill set through his work with both Opteon’s Residential and Government Services teams. Since January 2019, he has worked on a wide range of residential valuations across the Auckland region working closely with Richard Vaughan and Kris Vulinovich, as well as having a critical role in the success of ratings revaluation projects across the North Island. He now leads a team of valuers responsible for the completion of ratings valuation work in South Auckland.
Areas of Expertise
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Residential Property Valuations
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Valuations for Mortgage Security Purposes
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Government Services

Hayden Loughnan
Formal Qualifications
- Bachelor of Property - University of Auckland
- Bachelor of Commerce - University of Auckland
Industry Experience
Hayden has been working with Opteon since 2017 where he began working in data entry, updating and managing the commercial valuation database for Auckland, including sales and leases.
In his current role as Graduate Valuer, Hayden has gained experience in ratings valuations, inspecting properties via desktop and full internal, and updating the regional database. Hayden has undertaken Residential Valuations within the Auckland North Shore, specifically the North-West East Coast Bays location.
Hayden now completes ratings valuations for multiple regions, including processing subdivisions and building consents. He has also been teaching processes to new graduates.
Areas of Expertise
- Residential Property Valuation
- Valuations for mortgage security purposes
- Valuations for pre-purchase / pre-sale advice
- Ratings Valuation
- Market research

Shannon Aislabie
Formal Qualifications
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Member of the Property Institute of New Zealand
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Bachelor of Business with a Double Major in Property and Marketing- Massey University
Industry Experience
Shannon has been working for Opteon since October 2023, and has worked alongside the Government Services team, assisting with day-to-day exercises. She is involved in the residential property valuations and assists in ensuring all subdivisions have been put in place, building consents have been managed on selected properties, improvement values have been added to associated properties, and all sales coding has been updated. Shannon has begun her three years of training to become a Registered Property Valuer, including valuing Residential Properties, and out on field training.
Working in the Government sector, Shannon has completed valuations for Hamilton City Council, Matamata-Piako District Council, Taupo District Council, and South Waikato Council. She is excited and eager to progress in her career.
Areas of Expertise
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Residential Property Valuations
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Subdivisions
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Building Consents
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Sales Coding
Global Market Insights

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