Does not exist Dave.
It is the correct way of doing things simply because the business is in business to provide the service or part
so paying ahead of time will not make the business decide to opt out of providing the part.The chances are greater
that something may go wrong from the clients side simply because he is an individual and does not have a business
reputation at stake. It will still boil down to doing your homework when dealing with any business. If the feedback is good then
there is no danger in paying up front. IMO Jim is being too giving. Like you said Dave, he is risking at some point to
end up working for free.
Jules