No, asking for an invoice from the hospital doesn't work. I've learned that little lesson with Kim. His dad got into a motorcycle accident, so we went to the hospital to see him, and I ended up getting charged 2400 baht, even though I knew full well he was covered under the 30 baht program.

I didn't want to make a scene in the middle of a hospital though, so I just paid it, knowing full well I was being taken. Sure enough, on the ride home Kim decided to be honest, and let me know that his dad was going to go back to the hospital to collect that 2400 baht. I already knew that, but still, was nice of Kim to come clean about it.