I already said this in one of OP's other ambulance billing threads, but I got sent the bill from an out-of-network ambulance to the tune of something like $1200 for a 1.4 mile transfer from the hospital to a nearby facility, and eventually insurance paid them some $900 and the ambulance company seemed to go on their merry way after they called me one last time and I said "Don't you think $900 is adequate for a non-emergency transfer for 1.4 miles?". But I, y'know, actually called and talked to people at both my insurance and the ambulance billing company, I didn't just send a form letter and hope for the best.