Tools for Finding Comparable Sales for Investment Properties

Key Takeaways

• Tools for finding comparable sales fall into three groups: the MLS through an agent, free public sources (Redfin, Zillow and county records), and investor software (PropStream, Privy and DealCheck).
• The MLS, through an agent, has the most complete sold data and is the most reliable source of actual prices in non-disclosure states such as Texas.
• PropStream runs comps from public records and MLS data, with plans of $99, $199 and $699 a month and a 7-day trial; DealCheck runs comps from free to $20/mo.
• Goliath Data does not run comps or calculate ARV; it shows the owner, estimated equity and seller signals before the comps, then handles outreach, with plans from $1,499/mo.
• Fannie Mae requires appraisers to report at least three closed comparable sales and says sales that closed within the last 12 months should be used.

Goliath Data publishes this guide, and Goliath is one of the tools compared. Goliath does not run comps; it covers the steps before and after them. Prices and features were checked on each company's own site on November 5, 2026, and can change.

The tools for finding comparable sales on an investment property fall into three groups. The MLS, through an agent, has the most complete sold data. Free public sources (Redfin, Zillow and your county's records) cost nothing but have gaps. Investor software (PropStream, Privy and DealCheck) pulls comps and turns them into an ARV and an offer. Goliath Data sits around that step: it shows you the owner, estimated equity and the reason they might sell, then handles the outreach once your numbers work. You pull the comps in one of the other tools.

Here is what each tool does well, and how to handle states where sale prices aren't public.

What counts as a good comp?

Lenders set a useful floor. Fannie Mae requires appraisers to report at least three closed comparable sales, and says sales that closed within the last 12 months should be used.

A good comp also matches the subject property on what a buyer pays for:

• Location: same neighborhood, ideally the same side of any busy road.
• Size and layout: similar square footage, beds and baths.
• Age and condition: for ARV, compare against renovated sales, not the dated house next door.
• Sale type: skip family transfers and other non-market sales.

Comps matter more when prices are flat. NAR's September 2026 report put the median existing-home price at $417,500, up just 1.3% from a year earlier, with a median of 33 days on market. Investors and second-home buyers made up 20% of sales, and 27% were cash. In a market moving that slowly, an ARV that assumes appreciation is a guess.

How were the tools for finding comparable sales compared?

We used five neutral criteria:

• Sold-data source: MLS, public records or both.
• Non-disclosure coverage: whether it can show sale prices where the county doesn't record them.
• Deal analysis: whether it turns comps into an ARV, rehab budget or maximum offer.
• Outreach built in: whether you can contact the owner from the same place.
• Pricing model: free, monthly plan or through an agent.

Which tools find comparable sales, at a glance?

1. Goliath Data (before and after the comps)

Goliath does not pull comps or calculate ARV. It answers the questions on either side of that step: who owns the property, roughly how much equity they have, and why they might sell.

Each opportunity carries its seller signal: pre-foreclosure, probate, tax delinquency, equity and tenure, absentee ownership, or an expired or withdrawn listing. The source record stays attached. Records update hourly, though refresh timing varies by source and market. On iPhone, point the camera at a house to see the owner, years owned and estimated equity (Goliath for iPhone). Signals are reasons to look closer, not proof an owner will sell.

Once your comps say the deal works, you skip trace the owner and call, text, email or mail from the same CRM. David, Goliath's AI voice agent, can handle calls and configured follow-up, then hand the conversation to your team with the history attached.

• Pricing: Ramp $1,499/mo, Growth $2,999/mo, Scale $7,499/mo (pricing). That is a premium price that covers the data, the CRM and outreach tools, and setup by Goliath's team.
• Worth knowing: you still need a comps tool below. Coverage varies by county and record type, so check your counties in a demo.

2. The MLS, through an agent

The MLS is where agents report sold prices, and Redfin notes that MLS data typically includes actual sold prices and recent neighborhood comparables, including in non-disclosure states. If you aren't licensed, an investor-friendly agent can pull a comparative market analysis (CMA) for you. A good agent also knows which sales were distressed or off-condition. Ask for sold, pending and expired listings.

3. Redfin and Zillow sold data

Property pages on sites like Redfin show sale history, including previous prices and dates. They're free and fast for a first pass. Redfin's own guidance adds a caution: the figures may not reflect seller concessions, or may include closing costs. In non-disclosure states, a sold price may simply be missing. Use them to shortlist comps, not to set an offer.

4. County sale records

Your county's assessor and recorder keep the deed, and often the last sale price. Some counties let you back into the price even without one. In Los Angeles County, the documentary transfer tax is $1.10 per $1,000 of value, and the deed's first page shows the amount. A $660 county tax implies about $600,000 (unless the tax was computed on value less liens). It's free, but slow at scale. For working across many counties, see our guide to tools that combine county records across states.

5. PropStream

PropStream's Run Comps feature finds comparable sales using public records and MLS data, lets you filter them, and exports a PDF report. The same plans include an automated valuation model, an estimated wholesale value, and a Fix & Flip Analyzer that estimates costs, profit and maximum allowable offer. Plans run $99, $199 and $699 a month, each with a 7-day trial. Its strength is comps and list building in one familiar tool; see our PropStream review.

6. Privy

Privy is built around MLS data. Its help center says comps come "directly from MLS and other reliable sources," filtered by radius, date range and square footage, and grouped as active, pending, sold or withdrawn. Its distinctive feature is investor comparables: properties with a history of investor activity, so you see what local flippers actually bought and sold. MLS coverage varies by market, and we couldn't confirm current pricing on its site, so check both at privy.pro.

7. DealCheck

DealCheck is a deal analyzer with comps built in. Its pricing page lists sale and rental comps with ARV and rent estimates on every plan: up to 5 comps on the free Starter plan, up to 10 on Plus ($10/mo) and unlimited on Pro ($20/mo). It's a low-cost way to run the numbers on a flip or rental.

How do you find comps in non-disclosure states?

In some states, sale prices never enter the public record. Redfin names ten, including Texas, Idaho, Louisiana, New Mexico and Wyoming. There, only the buyer, seller and lender get the figure.

Texas shows how far this goes. The Bastrop Central Appraisal District says it lacks full sales data because Texas is a non-disclosure state, so its staff gather sales by contacting agents, brokers, sellers and buyers. If the appraisal district has to ask, a free website has the same problem.

What works in those markets:

• Lean on the MLS. An agent's sold data is the most reliable source of actual prices.
• Use tools that pull MLS data, such as PropStream or Privy, and check each comp's source.
• Treat a blank sold price on a free site as unknown, not as a comp.

How do you choose a comps tool?

• Free, early in a deal: Redfin, Zillow and the county site, then confirm with an agent.
• Sold prices in a non-disclosure state: an agent's MLS access, Privy or PropStream.
• Comps, list building and an offer calculator in one app: PropStream.
• Cheap ARV and rental math: DealCheck.
• The owner, estimated equity, seller signal and outreach in one system: Goliath Data, paired with any comps tool above.

Whichever you use, test it. Pick five recent sales in your market where you know the real price, run each through two tools, and compare the comps each returns. Sources and update timing differ by tool and market, and that test shows you by how much.