I have not read any of the replies so excuse if I repeat or am on a different angle than the topic has evolved to. IMO you owe helpers nothing but a big thank you and a chance to repay the favour back some time in the future....Most if not all people offer help and advice here free and without any obligagtion. It is our duty and pleasure as musicians to help advise and teach others..... we are all on a learning curve. Any help I offer is free of charge and I expect nothing in return other than the satisfaction of having been of benefit to a fellow musician. I would like to hope that if anyone made the big time from help someone gave they would try in some way to repay the debt...I know I would. I have never signed any proper contract and I often laugh when people make so much out of legal issues and contracts. What is hard about equal splits or paying someone what they deserve forthe work done?