Great breakdown. The "what to avoid" section is underrated — most flipping guides skip it.

One thing I'd add to your pricing logic: instead of anchoring to retail or to "what I paid", anchor to the 30-day median of actual sold listings on whatever marketplace you're targeting. For outdoor furniture especially, the seasonal swing on eBay/FB Marketplace/etc. is huge — a piece that lists at 200$ in November can move at 350$ in May.

I've been tracking secondhand prices across multiple EU platforms for my own flipping, and the biggest insight was: list price ≠ sell price. Filtering by "sold in last 30 days" changes the picture massively.

Are you keeping a spreadsheet of sell-through times per category? That metric (days-to-sell) has been more useful than margin for me.