Selling across marketplaces, written down properly
How stock actually behaves across Amazon, eBay, Allegro, Etsy and your own store — what breaks, what it costs, and the arithmetic behind the advice.
Multichannel selling ·
What happens to your listing when stock hits zero — Amazon vs eBay vs Allegro vs Etsy vs your own store
A side-by-side table of what Amazon, eBay, Allegro, Etsy, Shopify and PrestaShop do when your quantity reaches 0 — and what you lose on each.
Inventory management ·
Safety buffers vs stock reservations: what holding back three units actually costs you
What a 3-unit safety buffer costs per year, what an oversell costs, and when to buffer, reserve, or do both — with the formula and the arithmetic.
Inventory management ·
Your supplier's feed says 40. Your shelf says 6. Which number goes to Amazon?
You stock a SKU yourself and dropship it. The two numbers disagree. How to combine shelf, supplier feed and open POs without overselling.
Looking for setup instructions rather than analysis? Read the guides.
How we compare
Side-by-side on the things that decide it: oversell protection, per-order fees, and whose credentials your channels run on.
Channel setup guides
What each channel asks for before it will connect — which credentials, where to find them, and what to switch on once it validates.