Every vet is different even if they're all in the same town (kinda like gas stations they all Try to be lower then the competing station)
the vet i have near me (is not avian but sees birds) - 35 bucks is the fee for it to be seen, weighed and "looked over" all tests, nail clipping, beak trim etc is extra
Just a beak trim is $14
I haven't had to have any extensive tests done so I don't know how much those cost
then there is one over a hour from me $99 bucks gets your bird weighed, total grooming (wings of course is optional, beak and nails is only if needed), and the basic tests including blood tests, but it is just the basics - which isn't going to catch the major diseases most budgies end up with when they come to a new home.