5.0 MPI mercruiser w\ bravo 3. 300 hour service cost?

[RLWsnook]

Looking at some boats a few have this set up. the 5.0 mpi with bravo 3

I'm wondering what I should expect to pay for a 300 hour service from a mechanic. Ball park.

I'm no do it yourself kind of guy so I was wondering what I should expect to pay if I get a local person to do it.

TIA

AHH sorry I posted in the wrong forum.