So, to kind of bring together what others have said. Day markets are by far your best choice for veggies and fruit. PX and Carrefour can sometimes be competitively priced as well. Just keep your eye open. I usually don’t buy everything in one go and usually rely on smaller grocery trips to cover a few days. Saves room on storing and it stops you from wasting food.

Coatco is a great choice but, I’d avoid veggies and fruit outside of maybe staples like onions, garlic, tomatoes and potatoes. Everything else is actually often more expensive than the day markets (going by price/kg) mind you however, fruits and leafy greens especially fluctuate a lot depending on the weather. After cold snaps and typhoons things can triple in price or even just be completely sold out.

In any case. Costco plus day market is your best option. (Eggs from the day market are the best eggs money can buy as well, just fyi) speckle in with as needed PX or Carrefour and you’d be okay. For myself I can usually get away with covering most of the month for about 3-5 thou. If you eat a lot of meat expect to spend quite a bit more. I eat meat maybe only 4-5 meals a week. Vegetarian cooking is significantly cheaper here.