One of the go-to places in PI when it comes to seafood is Dampa, located somewhere in Pasay. You get to shop at a huge array of seafood in different stalls. And then you'll get to choose the restaurant to cook it all for you.
My parents have been to this places many times while this was our first (Me, Anna, Happy & Mommy). I've never really had that interest when I was still back here. But since I was gone for years, my longing for fresh (and cheap) seafood was unimaginable. We can't get this sort of food back in SD unless we spend at least a $100 for a meal.
It was perfect timing too since my dad's side of the family were also here in PI for the holidays. We had a feast that night. I bet that they missed this more than we did since they came from Canada.
Everyone had a blast. The food was great, but since there were several restaurants in the area, you really can't tell which was the best one. But if you're really in for seafood, this would be the place to go. I would say that for a party of ten, you're looking towards spending $150-$200. Depends on the variety of food that you want to eat.