What Is B3AF? The Watch Pricing Methodology Explained
B3AF (Bottom 3 After Fees) is a buy-side pricing anchor for watch dealers: the average of the three cheapest live listings for a reference, minus marketplace fees. Here is exactly how it is calculated and how to use it.
B3AF stands for Bottom 3 After Fees: the average of the three cheapest live listings for a watch reference, with marketplace selling fees deducted. It answers the only question that matters on the buy side — if I had to exit this watch quickly at the bottom of the current market, what would I actually take home? Price your buys against that number, not against asking prices, and a bad month becomes survivable.
Why asking prices lie to you
Open any marketplace and sort a reference by price. The spread between the cheapest and most expensive live listing for the same watch routinely exceeds 40%. Most of those listings will sit unsold for months — they are wishes, not prices. The only listings that predict your real exit are the cheapest few, because that is where the next actual sale happens. And even those overstate your outcome, because when you sell, the platform takes its cut first.
B3AF corrects for both distortions at once: it ignores everything above the bottom of the market, and it subtracts fees so you are looking at net proceeds, not gross. The result is a single conservative number that represents your realistic worst-case exit.
How B3AF is calculated
- Pull every live listing for the exact reference (same dial, material, and configuration — a two-tone Datejust is not a steel Datejust).
- Sort by total price including shipping and take the three cheapest legitimate listings. Discard obvious scams, franken-watches, and listings missing the reference number.
- Average those three prices.
- Deduct marketplace selling fees from that average. On eBay the fee structure is tiered: roughly 12.5% on the first $1,000, 4% on the portion between $1,000 and $5,000, and 3% above $5,000.
Worked example: steel sports reference with bottom three listings at $9,800, $10,100, and $10,400
| Step | Calculation | Result |
|---|---|---|
| Bottom 3 average | (9,800 + 10,100 + 10,400) ÷ 3 | $10,100 |
| eBay fees on $10,100 | 12.5% × 1,000 + 4% × 4,000 + 3% × 5,100 | $438 |
| B3AF | 10,100 − 438 | $9,662 |
The fee tiers matter more on cheap watches
Because the first $1,000 carries the highest rate, fees are proportionally heavier on a $1,500 watch (~10%) than on a $15,000 watch (~4.5%). B3AF bakes this in automatically — a flat "deduct 10%" rule of thumb overcharges expensive pieces and undercharges cheap ones.
From B3AF to a buy target
B3AF is an exit estimate, not a buy price. Buying at B3AF means breaking even in the best case. Dealers layer a margin requirement on top, and the discount you demand should scale with how long you intend to hold:
Standard B3AF buy-target ladder
| Strategy | Buy at | Typical use | Risk |
|---|---|---|---|
| Target Buy | 80% of B3AF | Default for sourcing — 20% cushion absorbs surprises and still leaves margin | Low |
| Holding | 90% of B3AF | Pieces you are happy to sit on while the market comes to you | Medium |
| At B3AF | 100% of B3AF | Fast flips only — sell at +5% or walk away quickly | High |
A robust buy price also cross-checks against auction results, because live listings can be temporarily distorted by one motivated seller or one optimistic cluster. A common formulation: take 80% of B3AF and 15% below the auction midpoint for the reference, and buy at the lower of the two anchors. When retail listings and verified hammer prices disagree, the conservative number wins.
Verified auction results provide the cross-check anchor for B3AF-based buy targets.
Where B3AF breaks down
- Thin references. With fewer than five live listings, the bottom three IS the market — one outlier swings the number badly. Lean on auction history instead.
- Condition mismatch. B3AF from three polished, no-box examples does not price your full-set unworn piece. Compare like with like or adjust explicitly.
- Fast-moving markets. B3AF is a snapshot. During a hype spike or a macro selloff, yesterday's bottom three is already stale — shorten your holding assumptions accordingly.
- Private-sale exits. If you reliably sell fee-free through your own network, raw Bottom 3 may be the better anchor — but most dealers should price assuming the marketplace exit, because that is the exit you can always count on.
Key takeaways
- ✓B3AF = average of the three cheapest live listings for a reference, minus marketplace selling fees — a conservative estimate of your realistic quick-exit price.
- ✓Never buy at B3AF expecting profit; the standard target is 80% of B3AF for sourcing, 90% for pieces you can hold.
- ✓Cross-check against verified auction results and take the lower anchor — listings show hope, hammer prices show truth.
- ✓Distrust B3AF on thin references, mismatched conditions, and fast-moving markets.