RPM, you may not be the only one on a payment plan.
This is a business situation by which you need to ask your self some serious questions about your man's ability to run a business.
Recommendations:
-Don't do anything with this Book until you're fully paid.
-Have the Book set a date when payment WILL be completed.
-Advise your Book that you are not a lending institution and his inability to pay as previously agreed is disrespectful towards you, suggesting that he should perhaps resolve your issue by visiting one of the many local lending institutions.
-Once you receive full payment, suggest reasonable compensation for the inconvenience of the loan.
-Upon full payment, institute limits on any future action involving this out, while I strongly suggest cutting off business ties entirely.
Conversely, these are just some of the actions taken by a Bookmaker towards Player in a similar situation.
Remember, it's only business.
Simple Game