How Multi-Unit Properties Are Actually Valued in Long Beach (A Buyer's Guide)
When I'm buying a multi-unit property in Long Beach, the first thing I want to understand before I write an offer is how an appraiser is going to look at it. Because the number the appraiser lands on isn't just a formality — it determines whether my financing holds, whether I'm overpaying, and whether the deal I negotiated actually survives escrow.
Most buyers assume the rent drives the value on a duplex or fourplex. And it does — but not the way you'd expect. Here's exactly how an appraiser works through a Long Beach multi-unit, using a real appraisal from the 90805 zip code as the example.
Step One: The Income Approach — What the Appraiser Does First
The first thing an appraiser does on a small residential income property is establish what the property should be renting for — not necessarily what it's renting for right now. This distinction matters a lot when I'm buying, because a seller with a below-market tenant doesn't get credit for the low rent. The appraiser is going to recast to market regardless.
This is formalized on what Fannie Mae calls the Small Residential Income Property Appraisal Report (Form 1025 / Freddie Mac Form 72) — the standard form used for 2–4 unit residential properties. The appraiser pulls three comparable rentals near the subject, compares unit size, bedroom count, condition, and rent per square foot, and establishes an opinion of market rent for each unit — what the unit would rent for today at arm's length.
On the Long Beach duplex I'm referencing, the appraiser pulled three rental comps within a third of a mile:
A duplex on Cerritos Ave, 0.28 miles away — two units at $2,500/month each ($5,000 total)
A duplex on E 57th St, 0.22 miles away — two units at $3,000/month each ($6,000 total)
A duplex on Myrtle Ave, 0.33 miles away — one unit at $3,200/month, one at $2,300/month ($5,500 total)
The subject property had one unit vacant and one occupied at $2,637/month — below market. The appraiser's opinion of market rent came to $6,000/month total: $3,200 for the larger vacant unit, $2,800 for the occupied one.
That $6,000 figure is what feeds the income approach.
The Gross Rent Multiplier (GRM)
Once market rent is established, the appraiser applies a Gross Rent Multiplier — derived from what similar properties actually sold for relative to their monthly gross rent. On this appraisal, the GRM came in at 142.
The math: $6,000/month × 142 GRM = $852,000 indicated value by income approach.
Here's the thing I always remind buyers: that $852,000 is a data point, not the answer. The appraiser noted directly in the report: "The Income Approach is typically given minimal consideration for this type of property, in this market." It's a sanity check — not the primary driver of value.
That's where the sales comparison approach takes over — and this is where the real number gets set.
Step Two: The Sales Comparison Approach — Where the Value Actually Gets Set
For residential properties with four units or fewer, appraisers use the same method as single-family homes: find similar sold properties, adjust for differences, and reconcile a value from what the market has actually transacted. When I'm underwriting a purchase, this is the number I'm watching.
On this appraisal, the appraiser used three recent duplex sales within 0.28 miles:
Comp 1 — 5575 Cerritos Ave: Sold for $880,000 (FHA, May 2025). Similar size and configuration. Minor upward adjustment for time and one fewer bathroom, minor downward adjustment for a larger garage. Net: +1%. Adjusted to $886,000.
Comp 2 — 1222 E 57th St: Sold for $955,000 (FHA, October 2025). Larger lot and a better quality rating triggered big downward adjustments — $31,000 for extra lot size, $20,000 for Q3 quality, $40,000 for C2 condition. Net: -10%. Adjusted to $864,000.
Comp 3 — 5341 Cerritos Ave: Sold for $845,000 (Conventional, October 2025). Cleanest comp — same bedroom/bath count, similar condition, minimal adjustments. Net: essentially flat. Adjusted to $844,500.
The appraiser reconciled those three — $886,000, $864,000, $844,500 — and landed at $845,000 as the final value by sales comparison.
The adjustment line items are worth knowing as a buyer, because they tell you how sensitive the value is to specific property characteristics. In this Long Beach submarket: lot size runs about $10/sq ft for differences over 1,000 sq ft, bedrooms at $6,000 each, bathrooms at $6,000 each, gross living area at $95/sq ft for differences over 100 sq ft, age at $100/year after the first 10 years, garage spaces at $10,000 per space, and condition rating — C2 or C4 — triggers a $40,000 adjustment either direction. That's not a small number.
The Final Reconciliation: Comps Win
With both approaches complete, the appraiser reconciled:
Sales Comparison Approach: $845,000
Income Approach: $852,000
Final Appraised Value: $845,000
They landed $7,000 apart — that's about as tight as it gets. The income approach confirmed the comp value, the appraiser gave most weight to comps, and the final number was $845,000.
The appraiser's own language: "Most weight is typically given to the Sales Comparison Approach for these types of properties. The Income and Cost Approaches were both correlated and given secondary consideration."
This is the dynamic I walk through with every buyer I work with on a Long Beach multi-unit. The income matters — a weak rent picture relative to comps can pull the income approach value down and create a disconnect with the comp number that gives the appraiser pause. But I'm not buying on a cap rate. I'm buying at a price that has to be supported by what comparable properties sold for, adjusted line by line.
What I'm Looking For as a Buyer
Below-market rents are my opportunity — not a valuation discount. The appraiser recasts to market rent regardless. So if I'm looking at a duplex where one tenant is paying $2,637 against a $2,800 market rent, the appraisal is going to reflect $2,800. That gap is my upside at lease renewal, not something that hurts the appraisal. I want to buy below-market rent situations, not pay a premium to avoid them.
Condition is negotiable; the adjustment is not. That $40,000 condition adjustment in this appraisal is real. If I'm looking at a C4-rated property, the appraiser is going to mark it down $40,000 relative to a C3 comp, full stop. I factor that into my offer — either I'm getting a price that already reflects deferred maintenance, or I'm planning to fix it and refinance after the value is reestablished.
Lot size is often underpriced by sellers. Adjustments run $10/sq ft for differences over 1,000 sq ft. On a 7,000 sq ft lot where the comps are averaging 5,500 sq ft, that's a $15,000 adjustment in my favor at appraisal that a seller pricing off a per-unit basis might not be capturing.
The permit record is everything. How an unpermitted unit or ADU gets treated at appraisal is not a small issue. Unpermitted improvements on a multi-unit don't get counted in GBA, can't be included in the income approach, and create lender flags that can kill financing. Before I go into contract, I pull the permit history. It's a 10-minute check that has saved me from bad deals.
I want to know what my lender will count. If I'm financing with a conventional loan, Fannie Mae's guidelines on comparable sales dictate how the appraiser builds the comp set. If I'm using a DSCR loan, the underwriting leans more heavily on actual income. Knowing which lens my lender is using before I write the offer tells me which numbers matter most on my analysis.
Why Long Beach Specifically Works Well for This
Long Beach has real, proximate duplex comp data. Three sales within a third of a mile, all from the last 12 months, ranging from $845,000 to $955,000. That's the kind of comp supply an appraiser can work with cleanly — which means appraisals here tend to come in predictably rather than wide.
Compare that to thinner markets like parts of Fullerton or Buena Park, where duplex comp sets are sparser and appraisers sometimes have to expand the geographic radius or go back further in time. Wider comp sets mean more adjustment variance, and more adjustment variance means less certainty on whether your offer price will appraise. Long Beach's active two-unit market is part of why investors continue to focus here for income property acquisitions.
The ADU Layer
Before I close on any Long Beach multi-unit, I want to know whether it can support an ADU. A permitted ADU on a duplex changes the income picture and the valuation in ways the standard Form 1025 isn't designed to fully capture on its own. How a multi-unit property gets valued when an ADU is part of the picture involves a different comp analysis — but the short version is that a permitted ADU adds a documented rent stream that Fannie Mae's ADU income guidelines allow to count toward mortgage qualification in certain scenarios. That expands my eventual buyer pool, which protects my exit.
This is part of the pre-offer due diligence framework I run on every investment property before I go into contract. ADU potential in Long Beach is a real value-add — but only if the lot and zoning support it, and only if the numbers pencil after you account for build cost.
The Bottom Line
When I'm buying a multi-unit in Long Beach, I'm not buying on income projections. I'm buying on comps, with income as a confirming layer. The appraiser is going to do the same thing — run the income approach first, then build the comp grid, then give most of the weight to where similar properties have sold.
Understanding that framework means I know exactly which variables to push on in negotiation: condition, lot size, below-market rents, permit history. The income is the story I tell the next buyer. The comps are what I pay today.
If you're looking at a specific Long Beach duplex and want to run the comp set before you write your offer, reach out — I'll pull the data with you.
Ready to Start?
Call or text Dylan Serna, ADU Realtor at (714) 860-2868 to schedule a consultation.
