I always look several times a day if not more.  I have bought and sold on eBay and you do get some special people that want everything for nothing.

Heaps of pics and a thorough condition report is the way to go. Most people know what the machine can do.

I would even think about a five day listing to encourage bidding. I know I have done it, put the machine in my watchlist and then lose interest or another machine pops up that catches my attention. Ending the auction on a Monday is also a good idea, how many guys have something on at 8pm on a Monday. It is a good time to have people glued to their computers bidding.