How much ROI should a Amazon Wholesale seller look for?

Hello guys, I am starting Amazon FBA wholesale, How much ROI do people who are FBA wholesale sellers looking for? At the process of starting this business I thought I could easily get 50% to 100% ROI with Amazon fees included but now that I opened a wholesale account with a big supplier in the US their wholesale products are expensive for example a product which sells for 20$ on amazon, the supplier sells it for 13$ wholesale. If I sell this product and then the amazon takes it fees which 6 dollars my net profit will be 1$. Can someone tell me if this wholesale price is too much or amazon wholesale is not profitable? I got LLC and resale certificate and weeks of products researching and finding suppliers and finding out that it’s not even profitable is so disappointing.