Include payment fee inside price (reseller)

Several products can be bought through the website, where each product is from a different vendor. I would like to charge vendor 1 e.g. a fixed handling fee per product, vendor 2 another handling fee, etc. Instead of charging the end user a fee.

Is there a way to arrange this? Or to get an easy overview of the total sales per category and/or the total sales minus fee.

Great! Thanks for the information.