A friend of the family passed away last week. He has a fairly big gun collection, 150+. His son has no interest or knowledge about firearms and wants my help to identify and assess value. More than likely I will be helping him sell the collection. The son, also said that if a fair price could be reached I could purchase the entire lot. I havn't seen the guns as of yet. Question: Is there any laws prohibiting me from such a purchase? Would there be any tranfers on paper or would cash and a handshake do?