A grocery store with a huge Heineken sign just north or Rino's Beach Bungalows. The name of the store is actually Rirei but there's no sign with that name.
What to buy: You can save money by cooking your own lunch and dinner since fully stocked kitchen is provided in Etu Moana. Grab a complimentary bike and start exercising! This store has a lot of stuff especially for tourists like me. They have things like pasta, tomato sauce, bread, frozen meat, dairy, vegetables, candy, rice, spam, corned beef, hot sauce, BBQ sauce, sodas, chips, ice cream bars, ice cream cones, liquors, canned food, frozen food, and a pretty good wine selection. These goods are flown in so they are pretty pricey. A can of spam costs around NZ$8 for example. If your lady gets her time of the month and she did not bring anything for it, you can find those here as well.
We ended up buying our groceries from this place than the bigger Maina Trader Superstore, just because there are more stuff for the tourists here in Heineken Store. We bought some pasta, tomato sauce, hot dogs, rice, spam, sodas, etc to cook with. It's much cheaper than eating at Tupuna's or Rapae Bay all the time.
What to pay: Expect to pay the usual tourist prices since the goods are flown in.