Underpriced AI vs eBay's free Terapeak: the $5 buys identification, not a better price

The short version: our reseller stack tells you to spend $0 on comps research, because eBay's sold-listings filter and Terapeak product research already answer the pricing question for most items. Underpriced AI is the most credible challenge to that advice we have seen, because it does something Terapeak cannot: you photograph an item you cannot name, and it tells you what it is before it tells you what it sold for. At $5 a month for 30 scans, that is worth paying for if you source at thrift stores and estate sales. It is not worth paying for a better number, and the vendor's own published accuracy grade is the reason we can say so. Prices as read on the vendor pages on 2026-09-30, so verify before subscribing.

What the vendor's own accuracy grade says

Underpriced AI does something we wish every pricing tool did: it publishes how far its estimates land from what items actually sold for, every week, wins and misses. We read the grade page on 2026-09-30, last updated 2026-09-29. These are the vendor's figures, not ours:

• 408 sales measured over the last 90 days. A sale counts when a user marks it sold or a listing published through the app sells on eBay.
• A 40% typical gap on the 214 sales where the seller set their own price. In their words, a $100 estimate sold for between $60 and $140 half the time.
• 43.5% of those sales landed inside the range the app showed. Across all 408 it is 61.3%, but that figure includes sellers who listed at the app's number, which the vendor itself calls flattering by construction.
• Category matters more than anything. Art (about 25% off) and antiques (about 30%) ran tightest. Toys (about 69%), vintage (about 65%) and pottery and glass (about 53%) ran widest. Every category is still marked too few sales to call.

The most useful table on that page is the one where the vendor sends the same first photo to general chatbots with no sold data. On the 79 sales ChatGPT answered, ChatGPT's typical miss on a $100 item was $33, and so was Underpriced AI's. Gemini ($30 against $25, on only 9 sales) and Perplexity ($43 against $33) both missed by more on the sales they answered. What separated them was the column beside it: the app showed real sold listings on 83% of results, ChatGPT on 0%.

So, read honestly, the $5 does not buy a more accurate number than you could get free. It buys speed to the evidence: identification from a photo, and the sold comps attached, so you can check the estimate the same way you would in Terapeak. The number is a starting point. The comps are the product.

Choose Underpriced AI if…

• You source at thrift stores, estate sales or storage units and regularly hold things you cannot name. Terapeak needs a search term, and an unmarked bowl has none. This is the one job the free route genuinely cannot do.
• You price on your phone in the aisle, where typing a Terapeak query per item is the slow part. Thirty scans a month is about 17 cents a scan at full use.
• You mostly sell on eBay and want the listing written and published from the same screen. Direct publishing covers eBay's US, UK, CA, AU, DE, FR, IT, ES, NL and BE sites, plus Bonanza.
• You sell records or fashion, where it adds a Discogs or Poshmark source that eBay data alone does not carry.

Stay on Terapeak if…

• You know what you are holding. Branded clothing, sneakers, books, electronics with a model number: the search term is printed on the item, and the free tool answers in the time it takes to type it.
• You already pay for Vendoo or List Perfectly. Underpriced AI's crosslisting overlaps with what you have, and its delist is a reminder rather than an automatic pull-down, so it would not replace the crosslister anyway.
• You sell in the categories where the vendor's own grade runs widest (toys, vintage, pottery and glass). You will be reading the comps yourself either way.

What the $5 changes in the stack. The reseller stack starts at about $22 a month. Adding Underpriced AI Starter makes it about $27. If a scan stops you walking past one item a month that would have cleared a few dollars of profit, the arithmetic works. That is arithmetic, not a test result, and it assumes you are sourcing unknowns, not relisting a closet you already understand.

One crosslisting caution, because it is the failure the reseller stack is built around. When an item sells on eBay, Underpriced AI detects it and reminds you to take the Poshmark, Mercari and Facebook copies down. The vendor is clear that nothing posts without you pressing Post, and the take-down is yours too. If a second buyer pays for something already in a box, the cancelled order counts against you, not the app. Run it as a pricing and eBay-listing tool, and keep a real crosslister if you list the same item in three places.

Name check before you sign up. A separate app listed on Trustpilot as Underpriced.App (a different domain, with different free-tier and price claims) turns up in the same searches. Everything on this page refers to underpricedai.com. And the vendor quotes two prices for its smallest no-subscription scan pack: 5 scans for $3 on its homepage, $4 in one of its own blog posts. Read the checkout, not either page.

Two other names in the same searches

What we have not evaluated

This page covers one challenger and the free incumbent, and it says nothing about the other photo-pricing apps (SoldScan, Pocket Pricer, Fuego Comps and others) or WorthPoint. We have not run Underpriced AI on our own inventory. Every accuracy figure above is the vendor's, published by the vendor, measured on the vendor's users. We think publishing it is to their credit, and we still would not treat it as independent.

Common questions

How much does Underpriced AI cost?

As read on underpricedai.com/pricing on 2026-09-30: the first scan is free with no card. Starter is $5 a month or $48 a year for 30 scans a month, Pro Plus $24 a month or $230 a year for 160 scans, Business $59 a month or $565 a year for 425 scans, and higher-volume Power ($99, 750 scans) and Scale ($199, 1,800 scans) plans exist. Scans past your plan cost 25 cents each, unused scans carry over for up to one month's worth, and every plan has a 30-day money-back guarantee. Scan packs without a subscription also exist, but the vendor quotes two different prices for the smallest pack, so check before buying. Verify on the vendor page before you subscribe.

Is eBay Terapeak free?

Product research is. eBay's help page says all sellers can use it from the Research tab in Seller Hub, with the last 3 years of eBay sales data. Sourcing insights, the category-trend view, is included at no extra cost for business sellers with a Basic Store subscription or above.

How accurate is Underpriced AI?

By the vendor's own published grade, updated 2026-09-29: on 214 sales in the last 90 days where the seller set their own price, the typical gap between the estimate and the sale price was 40 percent, meaning a $100 estimate sold for between $60 and $140 half the time. 43.5 percent of those sales landed inside the range the app showed. Toys, vintage and pottery ran widest; art and antiques ran tightest. We have not tested it ourselves.

Does Underpriced AI replace Vendoo or List Perfectly?

Not for a volume crosslister. It publishes directly to eBay and Bonanza, but for Poshmark, Mercari, Facebook and the rest a browser extension fills in the form and you press Post yourself. When an item sells on eBay it detects the sale and reminds you to take the other listings down. That is a reminder, not the automatic delist that Vendoo and List Perfectly sell, and the delist is the part that protects your seller metrics. The crosslister decision has its own page: Vendoo vs List Perfectly.

Is SaleFreaks allowed on eBay?

SaleFreaks describes itself as Amazon to eBay dropshipping software. eBay's dropshipping policy allows fulfilling orders from a wholesale supplier, and states that listing an item on eBay and then purchasing it from another retailer or marketplace that ships directly to your customer is not allowed. Read that policy before paying for any retail-arbitrage dropshipping tool.

See where comps research fits alongside crosslisting, photos and description drafting: The Reseller Stack →