Add the capability to see previous appointments each client has had with us.
And add notes to every appointment so it would be easier if job has to be done over few appoinments or client ask for exactly the same service as he got last time or before
bluegr Vasilis commented
Moreover, it will be great to send a survey to clients after the completion of teh service.
Ideally, I would like to have a spreadsheet of all appointments booked through the service. This could then be fed into Access.