He uses scoutly and has a small scanner

It instantly checks Amazon for profit based on the fixed book price. He would go when books were half off and just start scanning. Its crazy which ones have gone for $100+. One was a book about some European country's history after WWI. Niche books like that tend to be the ones that see significant returns.

Retail arbitrage seemed silly at first, but it has been a seriously dependable side hustle. It's a good way to build passive income. He watched a ton of YouTube videos in the beginning for tips. Amazon requires certain hurdles to get ungated in some categories. Once you're approved, you just send the product in to Amazon where they fulfill orders and ship. Basically everything you buy on Amazon was bought on clearance. It's the only way it works for us to cover shipping to Amazon and the fees Amazon charges to sellers. Brickseek is the app we use to check profits from clearance items. Hope that helps!