I recently won an auction on ebay for a macbook 1.83 Core Duo, 512 mb memory, 60 gig hard drive, Combo drive for $850. It is being sold by a seller who claims to be a Best Buy Outlet store (excellent ratings). The item is opened and is reported to "be in working order." I know that some of you ebayers hate guys like me who bid on an item and then have second thoughts...but I'm only in the market for a macbook for grad school this fall and have never used ebay before. I noticed that amazon has the same model macbook(new) for $999. Any advice?