A Martinez pricing comparison begins by identifying what each transaction actually conveys. A whole property with two dwellings, a separately owned accessory dwelling and an attached home on an individual lot can look similar in a search result while representing different ownership arrangements. Before assigning value to an upgrade or extra unit, establish the property interest, documented use and evidence of completed work.
The Martinez guide provides the broad setting. This article prepares a property-evidence file for a local broker’s analysis, using official records checked October 26, 2026. No permissioned MLS dataset, verified closing sample or private subject inspection was available. Consequently, the original asset is an unpriced comparability screen. It contains no invented closed sales, numerical adjustments or claim about current market direction.
Define the subject before selecting comparison properties
Write down the interest offered, existing dwelling configuration and significant obligations. Identify the living area being represented and separate any accessory space whose classification needs confirmation. State the actual selling objective and relevant timing. This gives a reviewer a subject to analyze; a list of nearby prices alone does not show whether those prices concern the same kind of property.
Next, label each source by what it establishes. An assessor record can help identify characteristics. A construction file can explain approved work. A recorded deed and related documents help identify the transferred interest. A current inspection describes observed condition. A verified sale record supplies transaction evidence. Combining these functions into one undifferentiated “property data” field makes it harder to detect a material mismatch.
A real separate-ADU example changes the comparison question
The 1735 Castro Street action minutes concern condominium conversion and minor subdivision of an existing residential site. The City’s 2025 housing progress report subsequently identifies the address as a separate-ADU ownership example. That is useful local evidence that an ADU label can coexist with a particular ownership structure. It is not a verified sale-price record for this article.
For valuation preparation, distinguish the sale of one dwelling interest from the sale of the whole original site. Do not divide a transaction price by combined area until the numerator and denominator describe the same property. Obtain the actual recorded configuration and appropriate transaction data. A correct area figure attached to the wrong interest can still produce a misleading comparison.
Common-area rights, repair responsibilities and restrictions should remain visible beside the physical description. Two homes with similar interior layouts may provide different outdoor rights or collective obligations. Ask the broker and other appropriate reviewers which differences affect the relevant buyer comparison. Without evidence of how the market treats them, do not convert an important document difference into an arbitrary percentage adjustment.
Alhambra Way shows why parcel and project status matter
The May 2026 Alhambra Way notice addresses a minor subdivision. The City’s project page separately identifies an incomplete major housing application. A seller preparing a comparison should preserve that distinction. The existence of one approval does not establish that every proposed dwelling or lot shown elsewhere is completed, separately transferable or available to compete with an existing home.
The broader lesson for a property with future-space potential is to compare the present offering first. Record the proposal as a separate feature with its actual stage and remaining conditions. Ask a qualified reviewer what the documents support. A drawing, an application and a completed improvement may each matter, but they do not provide interchangeable evidence of usable space or realized value.
Likewise, obtain title and subdivision evidence before relying on multiple assessor numbers as independent saleable sites. The County’s property-information resources are useful for locating and cross-checking records. They do not replace the review needed to determine the actual legal interest. An apparent land division should remain an unresolved comparison feature until the relevant documents support it.
Keep development pipeline separate from current closed sales
The Wyoming Heights approval letter records a tentative-map planning decision. That makes it relevant to understanding the local housing pipeline. It does not turn the planned homes into verified completed transactions. Do not insert proposed unit counts, marketing concepts or planning-stage dimensions into a closed-sale sample as though they describe delivered homes with established purchase prices.
The City’s current affordable-housing page also distinguishes approved pipeline projects from building permits. Recheck status for a live transaction because a public summary can lag. If a development has progressed, identify exactly what evidence changed: permit issuance, construction, occupancy or an actual closing. Each milestone answers a different question about whether the project is a present competitor.
| Local record | Comparison issue to resolve | Evidence to obtain before inclusion | Price treatment here |
|---|---|---|---|
| 1735 Castro Street condominium/minor subdivision action | One dwelling interest versus entire property. | Actual transferred interest, recorded plan, verified closing and matched area. | No price or adjustment; ownership screen only. |
| Alhambra Way separate minor and major applications | Current legal parcel and approved stage versus proposed buildout. | Recorded division and current application/building evidence relevant to the offered interest. | No assumed land-division premium or future-unit value. |
| Wyoming Heights tentative subdivision approval | Pipeline project versus completed competing transaction. | Current delivery, recorded ownership and actual sale evidence. | Excluded from closed-sale sample unless independently verified as a qualifying closing. |
| Waterfront negotiation process | Present amenity versus contingent future concept. | Actual relevant project milestone and market evidence for the subject. | No assumed future amenity premium. |
Sale dates, prices, concessions, area reconciliations and adjustment amounts remain unfilled. Public planning information does not supply those transaction inputs.
Separate an improvement’s cost from its market contribution
For the subject home, organize major improvements by scope, date, permit reference and current condition. Keep receipts where available, but do not equate expenditure with added sale value. A contractor’s charge answers what work cost under a particular agreement. The market comparison asks how buyers distinguish the resulting property from relevant alternatives, after considering condition, ownership and the evidence of completed work.
Where area is disputed, preserve each source’s description rather than selecting the largest number. Show which measurement includes an accessory unit, garage, converted area or another category. Ask for the appropriate reconciliation. A price-per-square-foot calculation is especially fragile when one property’s denominator includes space that another property’s denominator excludes. Resolve the classification before using the calculation to support a pricing recommendation.
Photographs can document visible finishes at a point in time but cannot establish every concealed system or construction approval. Give the broker the inspection findings and unresolved record questions alongside photographs. That allows the analysis to distinguish cosmetic presentation from broader work or uncertainty, without inventing a standard deduction for every missing document or a standard premium for every remodeled room.
Evaluate location claims at their actual stage
Martinez’s waterfront revitalization page describes an exclusive negotiating agreement and a study process. A negotiation milestone is different from a completed amenity or final development agreement. Keep the source and stage beside any forward-looking statement in the comparison file. An appealing concept should not quietly become a guaranteed feature of a current property’s location.
For existing destinations, test the route that matters from the actual property. Document access and observed conditions rather than assigning a universal convenience premium to all homes in a broad area. If the buyer pool appears to distinguish a particular route or setting, the broker should identify relevant transaction evidence. Proximity by itself does not supply a defensible numerical adjustment.
Build the actual closed-sale sample with a named reviewer
Once the subject is documented, have the reviewing broker state sample rules and the effective date. Record why each candidate belongs, the verified closing information, transferred interest and important differences. Keep excluded candidates with a reason. This makes the analysis reviewable and prevents a visually attractive but materially different sale from entering the sample merely because it supports a preferred price.
For common-interest property, include the relevant governing and financial evidence in that review. The Department of Real Estate’s current guidance supports looking beyond the physical unit. No private association records were obtained here, so the public examples carry no conclusion about dues, reserves or insurance. Those inputs need actual documentation when they matter to the subject and proposed comparisons.
Ask the broker to explain the evidence behind any adjustment and the sensitivity of the result to uncertain inputs. A range can still be unsupported if its endpoints are invented. Where the records do not justify a numerical adjustment, state the limitation and decide what further evidence is needed. The purpose is to make the reasoning inspectable, not to create a precise-looking worksheet prematurely.
Bring the resulting file into the selling process, with current transaction evidence and a named professional’s review before relying on a price recommendation. Use the Contra Costa County guide for broader context when alternatives cross city boundaries. The Martinez-specific preparation remains the same: identify the actual interest, reconcile the improvements and compare verified transactions that represent meaningful alternatives.
