6 - Marketplace
The marketplace is the place to exchange with buyers and sellers. The purpose of the site is to connect the two groups according to their specific needs, remuneration being in the form of commission, fixed or variable. Some examples of possibilities: auctions (eBay), classified ads (the seller pays the publication), reverse auctions (the buyer makes an offer that the seller is free to refuse), Research Offers (a robot travels the internet looking for the best offer), virtual shopping mall (several shops are on the same site and each seller pays its "location" in exchange for services managed by the site.
If your business model is not on this list, think about it several times and check your idea with other people before you begin. Better to be safe than sorry!
To Your Success!