Go for it.. It's all business. No guanratees that you'll get it of course. But, be ready with a lawyer in case "something" goes to court. "Someone" is gonna get sued.
You have to remember that people get sued for weird reasons. Your buddy might sue you for "tarnishing his image" or accuse you or wrong doings like stealing the computer before he could wipe it and such. Who knows.
This whack job recently sued NASA for $300 million for "altering the trajectory of the comet" slightly.. B/c she thinks it will change her astrological signs.. Or some shit like that.
i would do it jsut beucase that guy failed to meet the contact. and plus money in your pocket. and may i ask what do you do with these computer you used to get from that guy you sell them off.