Service fees based on Client

It would be nice to add a service fee based on clinet, I did look at predefine lines… however it is not based on the client… so instead of having a same service listed 120 times or so, it would be nice to have service fee based on client… (so when registering a user we would have the option to enter the service fee type and the amount…) in this case when creating invoice we could select the service and the fee will populate per client

Example
Defined service is Lawn Care

Client A fee is 35.00
Client B fee is 40.00
Client C fee is 60.00

So if client A is selected and service lawn care it would enter fee 35.00

If client C and service lawn care than it would be 60.00 and so on