My friend has a water-damaged MacBook Pro. It's a brand new base 15" inch model, less than a week old. Diagnosed with logic board failure due to a coffee spill. I took a look inside, removed the logic board, and it looks like I'll be able to clean it up and fix it. My friend has given up on it, and says he'll sell it to me for really cheap so I can repair it and gain from his loss. He asked me to make an offer. How much should I offer for such a machine?