Marketplaces are excellent landlords for small sellers and increasingly expensive ones for growing sellers. The trick is noticing which one you've become before the answer is obvious in your accounts. Four signals do most of the telling.
Commission is marketing you pay per sale. Early on it's brilliant — you pay only when it works. But when your monthly fees exceed what focused marketing of your own channel would cost (and you have repeat customers who'd follow you), the commission has quietly become the expensive option. Do the arithmetic annually: effective fee rate × yearly revenue, versus what that budget buys elsewhere. Under ~£2,000/year of fees, almost never worth disturbing; well past it, worth a think.
Every marketplace's audience has a price comfort zone. If your work has grown past it — your pieces now sit at the top of every search, priced double the neighbours — the platform's browsers have become the wrong buyers, and you'll feel it as compliments-to-sales ratio rising. That's not failure; it's graduation, usually towards a curated channel or your own site.
When customers return deliberately, the marketplace is charging you full commission for buyers it no longer supplies. Marketplaces forbid poaching (don't slip business cards into parcels against their rules — reputation is an asset), but they can't stop excellent products making people search your shop name. A meaningful repeat rate is the strongest own-channel signal there is.
If a suspended-account email would end your income this month, you're over-exposed regardless of how well it's going. That's not a reason to leave — it's a reason to add: the two-channel insurance pattern first, then perhaps an own-site presence that grows at its own pace.
The channel that built you keeps working while you add the next one. Shift new products, premium lines, or repeat-customer energy toward the new home; let the old channel keep doing what it does. Sellers who rage-quit a working marketplace to "go independent" overnight mostly rediscover why marketplaces charge what they charge — audiences are the hard part.
General guidance, August 2026. CAAC.