My 9 year old rottie mix had surgery a few weeks ago but it looks like the wound has some fluid build up in it, I'm going to make a vet appointment soon but I'm just wondering how much it'll probably be?
Presuming it's just a seroma, if you came to my hospital, the charge would be zero. A nurse would look at it and then aspirate the fluid. It takes all of about three minutes - no doctor required.
If they schedule you with the doc, plan on paying an office call fee. Hopefully they have a reduced fee for follow-up appointments.