Filemaker Pro bookkeeping/database

We are looking for someone to set up a bookkeeping program / customer database in Filemaker Pro.
This is almost as straightforward as they come. We are wedding photographers and customers book us upto 2 years in advance. At the time of booking, they pay a deposit and the remainder is split into two payments which would need to be paid 3 and 1 month before their wedding day. We need to know who has paid what, how and when. A booking should be added to our calender and not let it accept another one on tht day, a day later or the day before.
We do not keep any stock but we do want to know where our expenses ( Marketing, equipment, order fulfilment etc, ) have gone in detail and where our income has come from in details. The project should be delivered as a Filemaker project so that we can change it ourselves if and when we need to.
Many more details to be discussed.