How homes get priced: comps, CMAs, and appraisals

Ask three sources what a house is worth and you'll get three numbers: an online estimate, an agent's opinion, and an appraiser's report. Only two of those carry real weight in a transaction, and understanding how they're built lets you offer with confidence instead of guessing. Residential real estate is priced almost entirely by comparison — what similar homes nearby actually sold for — and once you can read comparable sales yourself, listing prices stop being intimidating and start being checkable.

The comparable-sales method

Both agents and appraisers price a home the same fundamental way: they find recently sold homes similar to the subject — 'comps' — and adjust for differences. A comp with an extra bathroom gets adjusted down to match the subject; a comp with a smaller lot gets adjusted up. Sold prices, not asking prices, are what count, because a listing price is just a hope until someone pays it. The best comps are close in location, size, age, condition, and style, and sold recently.

• Location: same neighborhood or school zone ideally, since location drives value more than finishes.
• Size: within roughly 20% of the subject's square footage, with adjustments for the difference.
• Recency: the more recent the sale, the better — stale comps miss market moves.
• Condition and features: updated vs. dated, garage, pool, lot size, and layout all get adjusted.
• Arm's-length: exclude sales between family or distressed sales, which don't reflect true market value.

CMA vs. appraisal: two comparison tools

A comparative market analysis (CMA) is what a real estate agent prepares — an informed opinion of value using comps, used to set a listing price or shape an offer. An appraisal is a licensed appraiser's formal, independent valuation ordered by the lender to protect the loan. Both rely on comparable sales, but the appraisal is the one that binds your financing: if it comes in below your contract price, the lender lends against the lower number. A CMA guides strategy; the appraisal governs the loan.

Reading comps yourself before you offer

1. 1
   Pull sold comps, not active listings

   Ask your agent for the last 90 days of closed sales similar to the home. Active listings tell you competition; sold prices tell you value.

2. 2
   Filter for genuine similarity

   Match location, size within ~20%, age, and style. Toss comps that are wildly different or clearly distressed.

3. 3
   Adjust for the obvious differences

   Mentally add or subtract for a missing bathroom, a finished basement, a bigger lot, or a recent renovation. You're normalizing everything to the subject home.

4. 4
   Build a range, then place the list price in it

   A tight cluster of adjusted comps gives you a defensible range. If the list price sits at the top or above, that's your negotiation opening.

The bottom line

Homes are priced by comparison to recent, similar, arm's-length sales — adjusted for their differences. An agent's CMA shapes strategy; the lender's appraisal governs the loan; the online estimate is a rough starting point and nothing more. Learn to pull and adjust sold comps yourself, build a defensible range, and you'll write offers grounded in evidence instead of anxiety — and see a low appraisal coming before it surprises you.