You can download a free 30 day trial copy and give it a test drive to better evaluate your ability to get it to work.
The key detail is to determine the number of simultaneous users of your database. A copy of FileMaker Pro can support simultaneous connections from up to four other users--each with their own licensed copy of FileMaker. To support more simultaneous connections requires hosting the database using FileMaker Server--either a copy your client purchases or ia a Hosting service. FileMaker server can also be used to publish the database to the Web via "Web Direct" and then your users can use a Web Browser to access the hosted database.