Easy solution. Go to a Wells Fargo office and pay the $5.00 check cashing fee. If they cash it, and you walk out of the bank with the loot. It's all good. Don't worry about the bank, there is no way that they will cash it if anything is fishy.
I just sold something on Craig's list and the person came by with a Wells Fargo bank check. Since it was for a very expensive watch I told him that we would drive over to the bank and cash it. He of course said "it's a bank check you don't have to worry about it". I told him that if there was nothing to worry about then he would have the watch in about ten minutes. He said he would go get a cup of coffee and come back in half an hour. Of course he never showed up again since the check was, of course, phony. I gave the bank the check, a copy of his e-mails and the plate number off of his car. If they follow up on it I will post and let you know what happened.
agree with oldmodman. you can check to see if the check ahs funds and also have them verify with the maker by calling them on the number they have on file. if they cant get a hold of him tell your buyer that the bank wasnt able to verify the check.