Guide
Most repricing advice focuses on speed — how fast can you match the lowest price? But the sellers who burn out on repricing do so because they moved fast without guardrails. The best practice that separates profitable automation from a race to zero is simple: define what you will never do before you define what the software can do. This guide covers the exact checklist — hard floors, competitor filtering, outlier detection, and cadence — that makes automated eBay repricing safe enough to run while you sleep.
A floor is not a preference — it is a constraint the software cannot cross under any circumstance. Calculate yours item by item before you configure a single repricing rule. The formula is: Cost + Shipping Cost + eBay Fees + Minimum Acceptable Margin = Floor.
Worked example: You source a phone case for $8.00, ship it for $4.00, and eBay charges ~13.25% of the sale price (final value fee + payment processing on a $20 item ≈ $2.65). You want at least 15% net margin on cost. That means: $8 + $4 + $2.65 + $1.20 (15% of $8) = $15.85 floor, rounded up to $16.00 for safety.
Until that number is locked in as a hard floor in your repricer, do not enable any automation. Every other best practice builds on this one.
Your repricer should never react to every listing that appears in search results. Low-feedback sellers, listings with no returns, drop-shippers with inflated shipping, and sellers listing a damaged or incomplete item all pull the apparent market price down below what a reputable seller should charge. Chasing those prices is how good sellers train buyers to distrust the category.
Before enabling repricing, audit who you are competing against. In Undercut you can restrict the competitor pool to sellers above a feedback threshold, with returns accepted, and with handling times within a defined window. Run this filter first, then let the algorithm work within that cleaned pool.
Outliers are single listings priced absurdly low — a competitor clearing dead stock, a data-entry error, or a seller who has already sold out but whose listing is still live. If your repricer is set to beat the lowest price unconditionally, one outlier pulls every one of your listings down with it.
The guardrail here is a minimum-price delta rule: only match or beat prices that are within a defined percentage band of the current median. If the median price for your item is $42 and one listing appears at $19, that listing is almost certainly anomalous. A well-configured repricer ignores it until at least two or three comparable listings exist at that level.
This is the single most underused best practice among high-volume sellers, and it is responsible for a disproportionate share of margin erosion events.
Not every category needs the fastest available cadence. High-velocity categories — consumer electronics, phone accessories, popular media — can see prices shift meaningfully within an hour. Slow-moving categories — vintage, antiques, collectibles, niche books — may not need repricing more than once per day, and repricing too aggressively in slow categories can signal desperation to buyers who are already doing price research.
Match your cadence to actual category behavior. As a starting framework: electronics and accessories benefit from 15-minute repricing; clothing, shoes, and general merchandise are well-served by hourly; collectibles, vintage, and antiques rarely need better than daily. Over-repricing is not a performance problem — it is a margin problem, because it trains the algorithm to chase noise.
The biggest mistake sellers make after setting up a repricer is treating it as a set-and-forget system. Markets shift, suppliers raise costs, eBay adjusts fee rates, and competitor pools change. A repricer operating on stale floors and outdated competitor filters will quietly erode your margin over weeks without triggering any obvious alarm.
Schedule a 20-minute weekly review covering three questions: (1) Have my costs changed for any active listing? (2) Are there new low-feedback or anomalous sellers anchoring my category prices? (3) Did any listing reprice more than 15% downward this week — and if so, why? This ritual catches drift before it becomes a problem and keeps automation safe over the long term.
No credit card required. Add up to 25 listings on the free plan and run the full guardrails checklist before you spend a cent.
Start freeHow do I calculate a safe price floor when eBay's fees vary by category?
Look up your category's final value fee rate in eBay's fee schedule, then add the 0.30 fixed payment processing fee per order. Build your floor formula as: landed cost + shipping cost + (sale price × category FVF rate) + 0.30 + minimum margin. Because the fee is a percentage of the sale price, you may need to solve for the floor iteratively — or simply add 2-3% buffer to your estimate to account for variation.
What happens if I forget to update my floors when my supplier raises prices?
Your repricer will keep competing at prices that no longer cover your actual cost. This is one of the most common causes of margin erosion among automated sellers — the automation is working correctly, but the floor inputs are stale. Build a cost-review trigger into your inventory workflow: any time a supplier invoice changes, that item's floor gets recalculated before the next repricing cycle runs.
Should I set the same repricing aggressiveness for all my listings?
No. High-turnover commodity items (phone cases, common cables) benefit from aggressive repricing to stay visible, while unique or scarce items (vintage, collectibles, limited-run products) have pricing power you lose by chasing every competitor. Undercut's Pro and Scale plans include AI aggressiveness tuning so you can set a different aggressiveness on each listing rather than applying a single posture to your entire catalog.
How do I handle a competitor who keeps pricing $0.01 below me?
First, verify they are in your competitor pool legitimately — check their feedback, return policy, and shipping terms. If they are a credible competitor, accept that some categories are price-efficient and focus on service signals (faster handling, better photos, more detailed descriptions) rather than trying to out-penny them indefinitely. If their floor is below your cost, your floor will stop the chase automatically. The goal of repricing is not to win every price comparison — it is to win the profitable ones.
Can I use Undercut's free plan to test floor-based repricing before committing?
Yes. The free plan supports up to 25 listings with no credit card required. That is enough to run your full guardrails checklist — set floors, configure competitor filters, and observe one full week of repricing behavior — before deciding whether to expand to a paid plan. Start with your 25 most active listings to get the most signal from the trial period.
Related: How to Avoid Selling Below Cost on eBay · How to Set an eBay Price Floor · What Is a Price Floor? · Repricing Without Losing Margin · Manual vs. Automated Repricing: Which Is Right for You?