Hey MF,
Gone are the days where a handshake agreement was a binding deal.
My opinion, leave it, If he asks you to do it again, then ask for payment up front plus amount still outstanding for previous cut.
I work in a trade industry (plumbing) where jobs are completed and invoices are sent out to customers. I hear many, many stories of the grievances caused from the little guys chasing money. As sad as it is to say, it is simply not worth it these days.
Just my opinion mate, good luck and make sure to let us know the outcome. Hopefully just an honest mistake on there part.
