if you want cash, fast i will do ebay. but i will do them 1 at a time. set the auction to end either a friday night, or a saturday night. then start the next one. you'll get the most money on weekends. with all rare games they usually go up and down, subsistence is good to sell right now since its really going for alot. and also alot of people are holding on to their copies now.
edit: also, if you end up selling on ebay, take good pictures and lots of them. i was watching an auction for 2 subsistence limited editions, one ended at $80, while the other ended at $160. cause the $80 had a bad picture. its weird, but it works.