We can address the tech issues involved in marketing a solution, but the marketing issues are a different challenge all together.
You might sell a run time version of your solution if a single user copy (no networking) and a few other limitations inherent to run times don't make that option unworkable.
You might sell a solution that requires the customer to buy at least one copy of FileMaker, multiple copies of FileMaker, multiple copies plus FileMaker server, multiple copies of FileMaker with a hosting service (could be YOUR hosting service) hosting the file. It might be a single copy of Server with Web Direct publishing the DB for clients using web browsers to access the DB, or it might be hosted from a hosting service via web direct.
So you have just a few options for how you might deliver such a solution. And it might be a "canned solution" or a basic "starter solution" that you then, for a fee customize to the needs of the specific client.
And then you have to figure out what method(s) you will use to deliver updates to your clients and whether they will be free or something they have to pay for...