One thing also to remember its the sellers choice who he wants to sell to. If after the first interested person claims dibs. (((( A 2nd or 3rd person Makes a substantial higher offer?)))
Absolutely. You can't be the guy that has no code, no honor. If you agree to something, you must stand by it. I've been offered more for stuff after I made a verbal agreement to sell and hold stuff. I have never burned a buyer that way. Those that don't abide by this are not cool. I almost hope they get flat tires on the interstate on a rainy day or a sudden bowel urge when stuck in traffic.