It looks good and I guess I remember seeing it on Reddit before , I can't understand If this is peer to peer or I'm selling to the owners of website themselves though ?
It's p2p. But they also have buy orders which let you instantly sell your item a little below the market price.
opskins also works if you are looking to sell items relatively quickly, although they do require verification and such just to withdraw, which is a hassle. Buy orders are not available on all items and they're usually set so low you're paying 60-65% for items, which is lower than quickselling your items ingame and selling to a key bot. Automatic selling is incredibly unreliable and it's really not worth doing.
