I name it Arctic Pyramid. I am allowed to upload a small 256x256 logo for my market. I decide to set my combined fully loaded fee at 3% per transaction between buyer and vendor.
I setup my categories, specify my escrow stealth address and my encrypted messaging support address and open for business.
Vendor X, goes in the wallet and browses the markets and decides to place his listing in Arctic Pyramid. He chooses a category and lists his product or service with all the details.
Buyer Z, goes in the wallet and browses the available markets, and selects the Arctic Pyramid market, and finds Vendor X's listing and places an order.
He creates a 2-of-3 multi-sig transaction containing the amount of the product or service and the market fee and sends it to the vendor, who signs it, and sends it to a key derived from the market stealth address.
After some auto-timeout period the market node will auto-sign and release the funds to the vendor, unless the buyer opens a dispute before the timeout period expires. Or, the buyer could choose to sign and release the funds before the timeout expires and close out the transaction.
After a transaction is successfully closed out the buyer and vendor may leave feedback for each other (similar to how localbitcoins works).
Maybe Vendor Y goes in the wallet and makes a listing for a product or service that I disallow or don't approve of. I can choose to block the listing, as part of my responsiblity as a market owner to be a curator.
Maybe when I open Arctic Pyramid I decide it is going to be only for art and my fee will be 15% because I provide concierge-level service through my encrypted messaging support address. And so I aggressively curate my market to make sure it is always clean with only high quality works of art, and I make sure to respond fast to customers through the support address and give them the VIP treatment. (I don't know anything about art actually, so maybe that's a bad example, but you get the idea).