"Can we just bring him in, and you can look at him real quick, and then let me know if he needs an exam?"
No. Either make an appointment and come in for the exam, or don't. I am happy to advise over the phone to an extent, eg: one episode of vomiting in an otherwise normal appearing young adult labrador retriever, probably ok to wait before coming in for exam; vomiting q 2 hrs x 48 hrs in a 12 year old cat with a history of FeLV, not ok to wait before coming in for exam. But, you can't come in to have me LOOK AT HIM to decide if you want an exam. Me looking at him = doing an exam.
Just wanted to clear that up due to a disturbing series of phone calls and drop-ins I've handled lately.