Using the formula on the EFT wiki to calculate the best price to sell my stuff at on the flea market for the maximum profit, I quickly figured I needed a way to automate the process. I made this for my own sanity more than anything, but I figured someone else could probably use it too.
If you input that you're selling 10 items that sell to therapist for 2942 (this example is the CPU fan) for 20k each, and click "calculate fee", you will see that you will pay 168,325 for the market fee and make 31,675 profit.
If you click "calculate max profit", you will see that your highest profit is 37,804 rubles, which you get from selling 10 CPU fans at 14,920 each. You shouldn't sell 10 CPU fans any higher than 14,920 each.
The market fee increases the more items you sell at once, so if you only sell 8 CPU fans in one listing, you should sell at 19,995 each for 52,272 profit. If you sold 10 CPU fans for 19,995 each, you would only make 31,687 profit, etc.
There are other factors in play, like Intelligence Center level. This script assumes you have level 3 intel center and level 9 hideout management for the Flea Market fees (because that's what I had when I made the script). Your own results may vary slightly.
I made it in vanilla JS (and TypeScript) and HTML, anyone is free to use whatever they want from it if they want to.
