Well, I can tell that six people are going to be in your room mashing their controllers to buy things as soon as you put them up. Those with the slightest lag will get nothing, and those with enough money to buy more than four or five items will just make money out of you.

There's no fair way to distribute things like this, you're best giving your stuff to friends, or some worthy souls of some kind. If you're just going to give the money away anyway, then you may as well not deal with the shop altogether in terms of putting things up for sale, and instead opt for individual personal trades. Also, you're talking a 1AM start time for those of us in the UK who have work :P