For the costs:
Ask your wife's gynecologist how much her fee is for both natural childbirth and c-section delivery.
Ask the hospital for options on hospital rooms (semi-private, private, suite, etc.) and how much they cost per day. Do remember that the higher the room cost, the higher the hospital fees. I wrote a blog post about this:
Natural childbirth is usually 2-3 days' stay at the hospital. For c-section, around 5-7 days.
Hospital fees vary depending on how much supplies, equipment, services you used, and the room you stayed in. You will know your total hospital fees once you've checked out. So ask your wife's gynecologist how much on the average it costs.
In addition to PhilHealth benefits, your wife can also get maternity benefits through SSS after she gives birth. Not much, but it's still something.
I would recommend getting a private room that would allow for your wife, the twins, you and 1 other companion (a trusted relative who knows how to take care of a child or a trusted yaya) who could cover for you when you need to rest or eat or in case the nurse can't understand your English accent. It would be best if the room has a refrigerator.
If you want to economize a bit, I would suggest bringing self-bought diapers, soaps, pillows, baby bottles, water, etc. if the hospital allows it. Beddings are changed only once a day. If you need them changed in between, you will be charged extra. So bring extra bed linens.
Security in some hospitals is lax. If you decide to room-in the babies, do not let them out of your sight. For example, if the nurse needs to give them a bath outside of your room or for check-ups / tests, you or your companion should follow them.
I'm 5' tall and my husband 5'10". For our first child, my doctor in the states recommended a c-section. She said that the baby might be too large, that I might eventually end up having a c-section anyways. But I insisted for natural childbirth. We even took birthing classes. Close to the due date, there were complications in the pregnancy discovered through ultrasound. The safer option for the baby was for a c-section. We opted for the c-section. With my second pregnancy, I had placenta previa. C-section was the only option.
I've read in many forums about people bashing women who opted for c-sections and for having epidurals. It really hurts moms when someone says that their c-section kid is less smarter than a natural childbirth kid. (there's one such comment in this forum from a male expat) or that women who have epidurals are weaklings. That's just bs.
In reality, c-sections are actually more painful. It takes a longer time to recover, longer time to get back in shape. Epidurals help women who have a family history of having long labors. to give them the strength to push the baby out when it's time so that they don't need to undergo an emergency c-section.
Do what's best for your wife and babies.
Our total hospital bill for a 5-day stay at a private hospital in Quezon City, including doctor's fees, 6 years ago for a c-section for our second child: PhP180k. Cheaper than US health insurance co-pay of US$3,600 + 900 for anaesthesiologist for our first child born in California. (Without insurance, hospital fees for our first child would have been US$43k.)
When you register your child's birth, make sure everything is spelled out correctly. In the Philippines, your middle name is your mom's maiden surname. Your children's middle name is your wife's maiden surname.