I don't think Google search requests are especially relevant here. A thing to realize is that people or businesses are looking for solutions and couldn't give a rat's ass if they run on FileMaker or on some other platform. For that reason I believe it's important to charge for the development of a solution as a whole. The software necessary just happens to be FileMaker. This doesn't deserve more than a line item on an invoice. Also all this assumes the purchaser will NEVER have full access to the solution. Spoken from the point of view of a non professional developer . . . but a pretty good one.