I'd suggest that was higher than it should have been UNLESS there were complications. You are entitled to ask! Having just had an £800+ bill from my vet, £600 sounds 'nice' BUT my boy was in from 8pm on a Sunday, on an I/V drip which he kept manageing to take out, until the following Tuesday morning when I collected him with a raft of pills. As he'd had numerous x-rays + pretty much 24/7 care and a scan which wasn't charged for, plus the Sunday emergency call out, I felt £800+ was justified. I'd gone to over £1K to be honest.
But there's no doubt vet costs are horrendous these days. Unfortunately at the outset, insurance wasn't an option for this hound. I did ask.
Fwiw, I'd NOT expect to have been told to go somewhere else - attitude. That's not good client-relations.
Add @ JC Isn't that pretty much the same ? Whatever, it 's not what I'd have wanted (or would!) from my vet.