My wife was recently operated on at Davao Medical School Foundation hospital. DMSF.
We had a firm quote which we paid upfront, which was negotiated with the social welfare and the billing department.
On release, the billing took 5 hours, they claimed an amount over and above the quote for an extra 28, 000 Php.
After 90 mins of arguing they reduced this amount to 5,000 Php.
A blog i am a member of for expats, suggests that foreigners are systematically over charged as a matter of procedure.
I would invite any feedback of your experiences and especially about DMSF.