The same product can be worth buying or worth skipping, and the difference has nothing to do with what you pay for it.
You know the feeling. You find a product with a 50 percent margin, you order 500 units, you build the store, you run the ads. And it dies. Not because nobody wanted it. Because the reviews said "still waiting" and the refunds started before the second batch arrived.
I got tired of guessing, so I built a scoring engine for it. Every product gets one number between 0 and 100. What surprised me was where the points actually sit.
Here is the same product, twice. Cost 12.50, sells for 24.95, margin identical in both runs. The only thing I changed is where it ships from.
5 days, EU warehouse -> 95 STRONG CANDIDATE
25 days, from China -> 50 MARGINAL
Same margin. Same price point. Same risk flags. Forty-five points of difference, purely logistics.
That is not a quirk of my weighting. It is the weighting. Margin is worth 35 points in the model. Delivery time and EU warehouse availability together are worth 45. I did not set out to build it that way. I set it up that way after looking at which products actually survived past the first month.
A thin margin costs you money once, on every sale, predictably. You can model it. You can price around it.
A three week delivery costs you in ways you cannot model. The chargeback. The review that sits on your product page for a year. The customer service hours. The ad spend you already burned on someone who cancelled. Amazon trained your buyer to expect two days, and your buyer does not care that you are a one person shop with a supplier in Guangdong.
The dropshippers I have watched succeed in the EU almost all made the same move at some point: they stopped optimising the margin and started paying for the warehouse. Their margin got worse. Their business got better.
Before you commit money, check three things in this order:
1. Can it ship from inside the EU? If yes, you have already won most of the points that matter.
2. What is the realistic door to door time, not the supplier's promise?
3. Only then, what is left after shipping and VAT?
Most people run that list backwards. They fall in love with a margin, then discover the logistics, then talk themselves into it.
The scoring engine is a free API. No key needed for the free tier:
curl -X POST https://api.insightoperator.org/api/v1/score \
-H 'Content-Type: application/json' \
-d '{"name":"Your product","cost_price":12.50,"sell_price":24.95,
"eu_delivery_days":5,"eu_warehouse":true}'Change eu_delivery_days to 25 and run it again. Watch what happens.
There is a Python SDK (pip install oscore), a JavaScript one (npm install oscore-check), and an MCP server if you want your AI assistant to score products during a conversation.
Scoring is one half. The other half is compliance, and that is where the expensive mistakes live. I put both into a 12 point checklist: what to verify before you spend a euro on inventory, including the VAT and Omnibus items most people find out about the hard way.
It is free and it shows up on your screen immediately, no waiting for an email: https://insightoperator.org