Picture the due diligence period on a well-kept four-unit building a few blocks off Castro Street. The rent roll looks disciplined. Increases came in steady and on schedule for the past six years, nudging upward a percentage point or two most Augusts. It reads like a landlord who understood the rules and worked them well. An investor underwriting the deal might reasonably assume that discipline is baked into the asset, that the next owner inherits the same trajectory.
That assumption is the part of Mountain View's rent control ordinance that catches buyers off guard. Some of what makes that rent roll look strong does not survive a change in ownership. The seller's rent roll and the buyer's rent roll are not the same document, even though they list the same units.
Which Regime You're Actually Buying
Mountain View voters passed Measure V in November 2016, creating the Community Stabilization and Fair Rent Act, or CSFRA. The ordinance took effect December 23, 2016, and it still governs the city's rent stabilization and eviction rules today. Coverage depends entirely on two facts about the building: how many units it has, and when it was built.
- Multi-family properties with three or more units built before February 1, 1995 are fully covered. That means both a capped annual rent increase and just-cause eviction protection.
- Multi-family properties with three or more units built between February 1, 1995 and December 23, 2016 get just-cause eviction protection only. No rent cap applies.
- Anything built after December 23, 2016, along with single-family homes, condos, and duplexes with fewer than three units, sits outside CSFRA entirely.
That third bullet matters more than it looks. A legal duplex in Mountain View, regardless of its age, is not subject to the CSFRA rent cap, because the ordinance's stabilization provisions kick in only at three units and above. A duplex might still fall under the statewide Tenant Protection Act (AB 1482) if it's more than 15 years old and doesn't qualify for one of that law's exemptions, but that's a different, generally looser cap. For a triplex or fourplex built in, say, 1988, the calculus is entirely different: full CSFRA coverage, a rent ceiling tied to inflation, and an administrative body watching the building's history.
That administrative body is the Rental Housing Committee, five appointed members who meet monthly at City Hall on Castro Street and hold rulemaking authority over the ordinance. They set the Annual General Adjustment, the CSFRA's rent cap, based on 100 percent of the change in the Bay Area Consumer Price Index each year. It is not a fixed number. The city's own adjustment history shows how much it moves: 3.4 percent for the 2017 to 2018 cycle, 3.6 percent the following year, 3.5 percent in 2019 to 2020, dropping to 2.9 percent and then 2.0 percent through the pandemic years, before jumping to 5.0 percent for 2022 to 2023. Buyers underwriting a CSFRA-covered building today should confirm the current cycle's figure directly with the city rather than assume a past year's number still applies, since the Committee resets it annually.
For buildings that fall outside CSFRA and instead rely on the statewide AB 1482 backstop, the math runs differently and, in recent cycles, higher. For the twelve months running August 1, 2025 through July 31, 2026, the AB 1482 cap sat at 5 percent plus the regional CPI of 2.7 percent, for a combined 7.7 percent ceiling, a cycle that has just closed out as of this writing. That's a wider allowance than most CSFRA-covered buildings have seen in a single year, which is worth knowing if you're comparing a pre-1995 triplex against a 2005-built fourplex down the street. The specific percentage resets every August 1, so confirm the figure for the current cycle directly with the city before you finalize an income projection. The build date isn't a footnote. It's the variable that decides which ceiling applies to your income projection.
The Number That Doesn't Transfer
Here's the mechanism that makes the opening scenario worth worrying about. Mountain View landlords are allowed to bank unused portions of their annual adjustment and apply them later, as long as the combined increase in any twelve-month window doesn't exceed 10 percent, per the municipal code governing the CSFRA. A landlord who holds rent flat for two or three years while the allowable adjustment accumulates in the background can, in theory, catch up all at once, subject to that 10 percent ceiling.
That banked value can make a rent roll look conservative and full of room to grow. It's tempting to read that headroom as an asset that transfers with the deed. It doesn't. The right to impose a banked increase does not carry over to a new owner when the property changes hands. Whatever cushion the seller built up resets to zero the day title transfers. The next allowable increase for the new owner starts fresh, calculated only from the current Annual General Adjustment going forward.
If a broker's pro forma leans on "significant upside from historical restraint," that upside likely belongs to the seller's ownership period only. Ask specifically whether any banked increases are reflected in the projected rent growth, and if so, strike them from your model. The city's own rent stabilization materials confirm this is a feature of the ordinance, not an oversight, and it's worth reading the full text of the CSFRA before you finalize an offer on any covered building.
The Frozen Lever You Might Inherit
A second detail rarely surfaces until later in escrow: registration status. Landlords of CSFRA-covered units must register annually with the Rental Housing Committee and pay a per-unit fee. Fall out of compliance, and the ability to impose any rent increase at all freezes until the registration is current. If a seller has been inconsistent about filing, a buyer can close on a building where the very first lever they want to pull, a routine annual adjustment, is locked until the paperwork catches up. Confirm registration status with the city's landlord resources page as a standard diligence item, the same way you'd confirm property tax status or code violations.
The Utility Line Item Almost Everyone Misses
One more wrinkle for older buildings specifically. In December 2023, the Rental Housing Committee adopted regulations clarifying that utility charges are part of rent for fully covered CSFRA units. Buildings that used a Ratio Utility Billing System, splitting a shared water or garbage bill across tenants based on unit size or occupancy, must transition that cost into a fixed rent amount through a one-time landlord petition process, at least for tenancies that started before March 1, 2024. If a seller's income statement shows separate utility reimbursement income for an older tenancy, that line item may need to be folded into rent and run through the adjustment rules rather than treated as pass-through revenue. It's a small detail on a spreadsheet, but it changes how a lender or an appraiser should treat that portion of income. The city's RUBS guidance page walks through the mechanics.
What This Means for the Offer You Write
None of this means CSFRA-covered buildings are bad investments. Mountain View's rental demand, driven by proximity to major employers like Google and LinkedIn, keeps occupancy strong regardless of which regulatory tier a building falls under. What it means is that the number on the seller's rent roll and the number you'll actually be able to charge in year one are two different figures, and the gap between them is defined by build date, banked increases that don't survive the sale, registration status you inherit, and utility billing history that may need restructuring.
Before you remove contingencies on any three-plus unit Mountain View property, get specific, current answers on four points: the building's exact construction date and which CSFRA tier applies, whether the seller has any banked increases they're implicitly pricing into the deal, whether registration and fees are current as of the closing date, and whether utility charges for any pre-March 2024 tenancy still run through a RUBS system. None of this is legal or tax advice, and the specific figures the Rental Housing Committee sets change annually, so confirm current numbers with the city and your own attorney before you finalize a purchase price.
A Few Questions Buyers Ask
Does CSFRA apply to a duplex? No. The rent stabilization and just-cause provisions only apply to buildings with three or more units. A duplex may still fall under the statewide AB 1482 protections depending on its age and other factors, but that's a separate, generally more flexible framework.
What about a single-family home with an accessory dwelling unit? Single-family homes are generally exempt from CSFRA rent caps under state law, though just-cause protections may apply depending on the tenancy. Confirm the specific configuration with the city, since ADUs can shift how a property is classified.
If I buy a building today, do I inherit the seller's registration history? You inherit the building's compliance status, not a clean slate. If registration lapsed under the previous owner, resolving it becomes your responsibility before you can impose any increase.
Is any of this legal advice? No. This is a due diligence framework based on public city records and the ordinance text as it stands today. Verify current figures and your specific building's status with the Rental Housing Committee and your own attorney before writing an offer.
If you're evaluating a small multifamily property in Mountain View, or thinking about what a CSFRA-covered building is really worth once the banked increases and registration status are accounted for, Real Smart Group works with builders and investors across the Peninsula on exactly this kind of underwriting. Get your free home valuation and a straight read on what you're actually buying before you write the offer.
