Well for contrasts sake... I visited BHP the other day.
In through the main door, immediately a very attractive young lady offered to help me, I handed over my card and told her the specialist type I wanted to see. (I like this approach, you get to see a specialist in a particular field rather than a GP, and being perhaps referred). She said please sit down in a comfy chair so I didn't have to join the riff-raff at the reception desk. After 10 minutes she retuned with a slip and my card and said please go up to a particular floor in building D. Had to wait 2 minutes for the elevator. Up there I presented my slip, and was told to wait, I was called after 2 minutes to go get the vitals checked and recorded, seems to be necessary every time you visit. Sit and wait again, for 10 minutes and called again to see a doctor. After seeing him asked to sit and wait and I made myself a free coffee. A lady then escorted me down to the ground floor cashier, here I waited 15-20 minutes before I was called, presented with the bill, money taken from my credit card, then immediately to the lady nearby to receive prescribed medication, 2 items.
Total cost 2271 baht, including the 2 lots of pills, in and out within an hour.
(Breakdown added later.....)
1431 Baht for medication (10% discount!)
50 Baht for 'Medical Equipment' I can only think it was for the ahhh-stick or his disposable gloves.
190 Baht Packaged Medical Charge, best guess the nurse taking my BP, asking me my weight and not caring of my height.
600 baht Physician Charge.
This time it wasn't suggested I had any expensive scans!
Your 'appointment' comment seems to tie in with what I was told happens at The Queen Sirikit up in Sattahip.... everyone gets an 8am 'appointment' but it is really first come and then queue.