Expert Witness  ·  Eminent Domain  ·  Litigation Support  ·  California

California Certified General Appraiser.
Retained by Attorneys in Complex Valuation Disputes.

William Martinez provides independent real estate valuation opinions for attorneys and courts throughout California — eminent domain and partial takings, estate and gift tax, conservation easements, and fractional interest disputes. No lending assignments. No institutional conflicts.

Available for consultation and engagement on active litigation and valuation matters throughout California.

William Martinez, MRICS, ASA  ·  California State-Certified General Appraiser  ·  Federal Courts

William Martinez | MRICS | ASA | AI Candidate for Designation | 20+ Years | California · Federal Courts | UK · Cross-Border

Independent practice, no lending assignments. Our practice accepts no mortgage lending work. Every engagement is for litigation, tax, or advisory purposes — so our opinions are not shaped by lender timelines, AMC fee structures, or institutional relationships. When independence is tested, it holds.

Who We Serve

Who We Work With

Property Owners

If your property's assessed value is higher than what the market supports, you are overpaying taxes. If the government is acquiring your property through eminent domain, you are entitled to full and fair compensation under the law — an independent appraisal determines whether the offer reflects that standard.

We provide independent valuation support for assessment appeals in California (expanding), and for condemnation matters where the stakes justify professional representation. You are not required to accept the value the assessor or agency puts in front of you.

You are not required to accept the number the assessor or agency puts in front of you. An independent analysis establishes what the evidence actually supports.

Attorneys

You need an expert who builds a defensible opinion, holds under cross-examination, and communicates complex valuation methodology to a judge or jury without losing the room. We work with plaintiff and defense counsel on real estate disputes, condemnation proceedings, partnership dissolutions, and fraud matters.

Our analyses are prepared to litigation standards from the first draft — not retrofitted after the fact. Expert testimony admitted in California Superior Court. Appearances in U.S. District Court.

The difference determines whether your valuation is admitted, challenged, or discounted.

CPAs & Estate Planners

Date-of-death valuations, fractional interest discounts, conservation easement deductions, and gift tax appraisals all carry IRS exposure. You need an appraiser who understands the valuation theory behind minority interest and lack-of-marketability discounts — not just someone who fills in a form.

Our reports are written to withstand audit challenge and, if necessary, Tax Court scrutiny. We work directly with counsel and advisors to ensure the valuation supports the strategy.

A poorly supported valuation doesn't just fail — it can expose your client to penalties.

What We Do

Practice Areas

No Surprises

How Engagements Work

01

Initial Call

Fit and scope in under 10 minutes. We'll tell you whether the matter is a match and what an engagement would involve — no obligation.

02

Engagement

Data collection, site inspection, comparable analysis, and workfile development. The analysis is built to litigation standards from day one — not retrofitted later.

03

Defensible Opinion

A written opinion supported by a complete workfile — ready for deposition, IRS review, or board hearing. We stand behind the number under cross-examination.

William Martinez, MRICS, ASA
Since 2005

About the Principal

William Martinez, MRICS, ASA

William Martinez is a real estate appraiser and expert witness with two decades of experience in litigation, tax, and advisory valuation. His practice is built on a single principle: every opinion must be defensible under the most rigorous scrutiny — whether in a courtroom, before the IRS, or before an assessment appeals board.

His MRICS credential — awarded by the Royal Institution of Chartered Surveyors — places him among a few U.S. appraisers recognized internationally, positioning the firm for cross-border matters and the firm's planned UK expansion.

MRICS — International Credential

One of a few U.S. appraisers credentialed by the Royal Institution of Chartered Surveyors. Qualified for cross-border, UK, and international valuation matters — a rare capability in domestic litigation and tax practice.

MSc Candidate · Manchester (exp. 2027) MRICS ASA Candidate for Designation · Appraisal Institute USPAP California
Full Biography →

Confidential · No Obligation

Have a matter that fits? Let's talk.

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Independent Appraisal Review

Opposing Report Already on File?

Attorneys often come to us mid-case with an opposing valuation already in hand. We conduct an independent appraisal review under USPAP Standards Rule 3 — examining the work for completeness, accuracy, adequacy, and reasonableness.

Where material deficiencies exist, we develop an independent opinion of value supported by a complete workfile and prepare to present it. The reviewer's role is to provide objective analysis — that independence is precisely what makes the testimony credible and durable under cross-examination.

Learn About Appraisal Review

What We Look For

  • Unsupported adjustments in the sales comparison
  • Income approach — cap rate and rent assumptions
  • Comparable selection bias or geographic stretch
  • USPAP compliance gaps
  • Effective date and retrospective value issues
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Get Started

Ready to Discuss an Engagement?

Contact us for a confidential, no-obligation conversation. We'll tell you quickly whether the matter is a fit and what an engagement would involve.

Discuss an Engagement →
San Rafael454 Las Gallinas Ave #1082, CA 94903
Los Angeles3680 Wilshire Blvd, Ste P04, CA 90010
London275 New North Rd, Islington #1256, N1 7AA