Refund firms keep up to 25% of what Amazon owes sellers. Refunzo keeps 15%.

AMAZON SELLER REIMBURSEMENTS · 8 MIN

Refunzo, the reimbursement service run by Brijesh Singha and Jimi Patel, scans an Amazon seller's account for free and files claims for 15% of what Amazon pays back, capped at $5,000 per account, versus the 25% Seller Investigators charges. Refunzo says it has recovered $10M+ for sellers. The terrain is the money Amazon owes for stock it lost, damaged, or refunded without getting back, and it stayed open because finding each unit means reading reports most sellers never open.

Every week, some of a seller's units go missing inside an Amazon warehouse, get damaged in handling, or are refunded to a customer who never sends them back, and Amazon owes the seller for each one. For years, a bookkeeper or specialist firm found that money by downloading Amazon's inventory reports, matching every missing unit against the reimbursements Amazon had already paid, and opening a support case for each gap. Refunzo does the matching with software. A seller connects the account, and a free scan checks it across what Refunzo calls 21 checkpoints, returns an itemized report, and can be rerun any time, with no card required.

From there, the seller chooses. The do it yourself plan costs $0: the seller takes the report and files the cases with Amazon. The managed plan has Refunzo's staff file them, and it charges 15% of what Amazon pays out, billed only after Amazon credits the seller's bank account for a specific case, with the total capped at $5,000 per account. Refunzo comes from eStore Factory; its co-founders are Brijesh Singha and Jimi Patel, and its home page says a 70-person specialist team handles cases. The pricing page also tells sellers recovering under roughly $2,000 a year that filing the cases themselves usually costs less, which is unusual for a contingency service to print about its own product.

Amazon's 10-K for 2025 reports $172,162 million in third-party seller services, which it describes as commissions plus the related fulfillment and shipping fees, or 24.0% of its $716,924 million in net sales. The FTC's amended complaint against Amazon says the company "reportedly takes close to half of every dollar from the typical seller that uses Amazon's fulfillment service." When Amazon loses part of that seller's stock, it owes the money back, and a second group of firms takes a share of the refund before the seller sees it. GETIDA advertises pricing "starting at 20%", Seller Investigators charges a 25% commission, and Threecolts' Margin Pro charges 15% to 25% depending on volume and contract term and says it has recovered more than $500M for FBA sellers. Refunds Manager, which also works with large vendors, claims it has recovered $800M.

The toll existed because every refund depends on a seller noticing a gap across separate reports for inventory adjustments, reimbursements, customer returns, and removal orders, and then filing before a deadline. Amazon's own staff guide, posted in its seller forums in August, says warehouse losses must be filed "within 60 days of the date the loss or damage event appears in your reports" and inbound shipment shortages within 9 months. Few sellers have anyone reading four reports weekly, so paying a firm to do it for a share of the refund was worth it.

Amazon then took the easiest claims for itself. On November 1, 2024, it began reimbursing units lost in its fulfillment centers automatically, without a claim. Effective March 31, 2025, moved back from March 10, it began paying for units lost or damaged before a customer order at the manufacturing cost, which it defines as the seller's cost to source the product, excluding shipping, handling, and customs duties. Both changes cut the dollars a percentage firm earns per claim, and both leave the remaining money in returns, removals, and inbound shortages, which still need a case. The latest move is that August guide, which tells sellers that if a customer was refunded and the item never came back, "in most cases we'll charge the customer and reimburse you," while the cases that slip through still have to be filed by hand.

The price advantage lies in cases Amazon still will not pay on its own, where each claim is worth less and only a provider whose cost per case is close to nothing can afford to file every one.

A mention here is listed, never sold.

LISTED · FBA RECONCILIATION AND CLAIMS

Refunzo connects to a seller's Amazon account, runs a free scan across 21 checkpoints, and hands back an itemized list of units Amazon lost, damaged, or refunded without a return. Sellers can file the cases themselves for $0, or let the managed team file them for 15% of what Amazon pays out, charged per case after the money lands and capped at $5,000 per account. The home page says Refunzo has recovered $10M+ for sellers, a figure it does not date. Co-founders Brijesh Singha and Jimi Patel also run eStore Factory, the company Refunzo comes out of.

Reach them · refunzo.com · About and founders

LISTED · DONE FOR YOU REIMBURSEMENT SERVICE

Seller Investigators, co-founded by Lee Loree, Robert Ferreira, and Ritchie Diputado and now part of the Carbon6 group, does the whole job for the seller: a free audit within 48 hours, then its team files and follows up on every case, for a 25% commission charged only after the reimbursement arrives. It says it finds more money than competitor services for 99% of its new customers. The contrast with Refunzo is the fee structure: for a seller who recovers $50,000 in a year, Refunzo's own comparison table puts a 25% firm's fee at $12,500 against its own $5,000.

Reach them · @seller_inv · LinkedIn · Founders

Take one seller and one year. Assume a seller does $1,000,000 in FBA sales (for this example), and use Margin Pro's published estimate that recoverable reimbursements run 1-3% of FBA revenue; at 2%, Amazon owes that seller $20,000. The service's take rate, the share of each transaction dollar that a middleman keeps, determines how that $20,000 is split. At Seller Investigators' 25% the seller pays $5,000, at GETIDA's starting rate of 20% it pays $4,000, and at Refunzo's 15% it pays $3,000. Refunzo's cap starts to matter once recoveries pass $33,333, and past that point its effective take rate falls: at $50,000 recovered it charges $5,000, which is 10%, against $12,500 at 25%.

Now the provider's side. Cost to serve is what it costs the provider to deliver one more unit of its service, which here is one filed case. Since March 31, 2025, a unit lost before a customer order is repaid at manufacturing cost, so assume a unit that cost the seller $9 to source (an assumption). A 25% fee on that claim is $2.25, and a 15% fee is $1.35. If a person spends 15 minutes on the case at $20 an hour (both assumptions), the case costs $5 to work. Contribution margin, the revenue from a sale minus the variable costs of delivering it, is negative on every small case a person works by hand, which is why services skipped or bundled them, and why Amazon's switch to cost valuation pushes this business toward software that matches the reports and drafts the case text at almost no cost per case.

For the build to make money at scale, software has to find and draft nearly every case so that people handle only the disputes, every case has to be filed inside Amazon's window, and the price has to sit below the 20% to 25% the done for you firms charge, because a free scan with a capped 15% fee is now on the market.

The narrowest wedge is the refunded return that never came back. Amazon says it charges the customer and reimburses the seller in most cases, so the remaining money sits in the exceptions, which nobody at Amazon chases for the seller. Build a nightly job on Amazon's Selling Partner API that pulls three reports (GET_FBA_FULFILLMENT_CUSTOMER_RETURNS_DATA, GET_FBA_REIMBURSEMENTS_DATA, and GET_FBA_FULFILLMENT_INVENTORY_ADJUSTMENTS_DATA), matches each refund to a restock or a reimbursement, and drafts the case text for every gap with the order and the dates attached. The only integration that matters is API authorization, so the seller grants report access through Amazon and never hands over a password. Do not file anything automatically; send the seller a list to approve each morning. Charge a flat $29 a month (our suggestion, not a market price) so the seller keeps every dollar Amazon returns, and call a private label seller doing low seven figures who tracks returns in a spreadsheet and has never hired a service because a quarter of every refund felt like too much.

RECON · TWO TERRAINS WHERE THE TOLL STILL STANDS

Two jobs where an incumbent still collects and no builder is standing yet, found this week with the sources attached.

RECON · OCEAN DEMURRAGE AND DETENTION

Since May 28, 2024, a Federal Maritime Commission rule has required an ocean carrier to send a demurrage or detention invoice within 30 days of the last charge and to give the importer at least 30 days from the invoice to ask for a refund or waiver. Carriers collect these charges: MSC's U.S. tariff lists import demurrage at Long Beach from $65 to $150 per container per day after the free working days run out, and detention from $165 to $230. The carrier writes the invoice and will not audit itself, and Windward's tool audits invoices without filing anything. Build an agent that checks each invoice against the rule and files the dispute in time. Charge 20% of fees waived, and call a mid-size importer's logistics manager.

RECON · MEDICARE INCOME SURCHARGES

CMS's fact sheet of November 14, 2025 sets the standard Part B premium at $202.90 a month for 2026, and an individual with income of $500,000 or more pays a $487.00 monthly adjustment on top, for $689.90, up to $5,844 a year in surcharge. The surcharge follows the income brackets in that table, and it stays in place unless the retiree files Form SSA-44, revised in December 2025, showing one of eight events such as work stoppage or loss of pension income. Medicare has no reason to lower its own bill, and the retiree has to know the form exists. Build an agent that interviews the retiree, gathers proof, and fills in the form. Charge $149 flat, and call fee-only financial planners whose clients retire this year.

saleweaver/python-amazon-sp-api is a Python client for Amazon's Selling Partner API with synchronous and asyncio versions, and its report types include the inventory ledger, reimbursements, inventory adjustments, and customer returns reports this build needs. It has 682 stars, an MIT license, and its last push was October 3, 2026. It is worth an hour because pulling your own account's reports through it tells you, before you write any matching logic, how many gaps a real seller has and whether the build is a weekend job.

The fraud in this business runs through the access the seller grants. A reimbursement service gets into the seller's Amazon account to read reports and open cases, and with that access a dishonest or compromised provider can file claims for units the seller never shipped, inflate the cost basis, or open dozens of cases in a day, and every one of those claims goes out under the seller's name. In fraud work, this is the insider position: the party trusted to recover the money is also the party best placed to invent a claim and keep a share of it. The one control is a record the provider cannot write to. Match every case to the seller's inbound shipment and cost records before filing, and require the seller's approval for each filing, logged with who approved it and when.

PASS IT ON

Think of the friend who sells on Amazon and has never opened the inventory adjustments report. Amazon may owe them money, and the 60 day clock is already running.

NEXT ISSUE

Agents that collect on late parcels. FedEx suspended its money-back guarantee on December 1, 2025, and brought it back only for some services on January 13, 2026; LateShipment says it found 18,503 refund-eligible FedEx opportunities across 4.7 million shipments. Who keeps the refund, how short the claim window is, and what an agent that checks every tracking number earns.

SOURCES

Amazon 2025 Form 10-K · FTC amended complaint v. Amazon · Amazon reimbursement policy update · Amazon effective date notice · Amazon automatic reimbursement announcement · Amazon staff claims guide · Amazon SP-API FBA report types · Refunzo pricing · Refunzo home page · Refunzo about page · GETIDA pricing · Seller Investigators home page · Seller Investigators about page · Threecolts Margin Pro · Refunds Manager home page · Federal Register FMC billing rule · eCFR 46 CFR Part 541 · MSC U.S. detention and demurrage tariff · Windward D&D automation · CMS 2026 Part B premiums · SSA form SSA-44 · FedEx money-back guarantee · LateShipment FedEx refund data · GitHub saleweaver/python-amazon-sp-api