Wow hot one.
I have been holding a set of rims for about a month for someone, he keeps in contact and I will let him know if any other offers are on the table. It couldn't have hurt to let Pauls brother know that there was another buyer and give the first buyer a day or so to show up. Prevents this mess and tarnishing of your name. Money talks yes but when your rep is shit no one will put up there money.
I have had people on this board hold parts for me while I get cash and I am super greatful they did, I understand that all sellers cannot be like this but if they are they should state that the sale is first come first serve, and not assume the buyer knows this.