The Dummy understands the project is a great occasion and agrees on paying, with his hours spent on the project, for a sure investment that in the “future” will eventually return something.
The Dummy should consider the payment as a favor since The Client already pays back showing the project and providing visibility to the otherwise unknown Dummy.
Further the spendthrift Dummy should also thanks the Client since the payment is delayed in comfortable and convenient installments to be considered as a constant revenue dispenser.