I’m fortunate enough to have a great tech. Very honest, unbelievably affordable and he always takes the time (before and after) to explain the process and then go over the bass with me before I leave. And if I discover that something isn’t quite right (I never have yet), he gives me 30 days to bring it back and he will correct it at no charge. He once relocated a string tree that was off center by drilling a new hole in the headstock and filling the old one, of course. He then created a notch for easy trussrod access... all this stuff was done to my 60s Fender J (reissue). This involved carving a bit of the body out and notching the pickguard. He painted the carved area with black paint to make it looked “finished”. Totally professional job. All that for under $60! Otherwise, I do my own setups. And as others have mentioned, someone else will never get your bass setup exactly the way you like. It pays to do your own setup work, for sure.