So if you don’t know, what Cosco is: It’s basically the Metro of the USA. If you don’t know, what the Metro is,  I’ll explain it to you.
Cosco is a huge company with thousands of products. You take a membership for 50$ and then are free to go in. Without membership no shopping. But the 50 bucks are totally worth it, because most things are a lot cheaper. From the inside it’s like a warehouse. They have everything from electronic devices to food. Also cool is, that you can buy for example a surfboard, enjoy it during the whole time in Hawaii and then return it (used) at the end of your vacation and get your money back. So what we did, was a membership, because we wanted to buy a GoPro there, which was unfortunately sold out. But we found an even better camera with actual features for taking great photos. The camera can do everything and there were all kinds of equipment, that one usually had to buy separately.
It was already later than we had planned, but we went to Waikiki Beach anyway. It is wayyyy overrated! I mean, of course you should have seen it once when you are on Oahu, but once is enough. On the beach you walk passed many american tourists, who live in the hotels right behind them and probably haven’t moved more than from their room to the elevator, from the elevator to the beach and from the beach to the next Burger King and back (this is not an offense against the Americans in general, but against the ones, that I saw at the Waikiki beach. And in a way, I have to be grateful, because therefore all the other beautiful beaches are pretty much empty). Other than the beach there is not too much to see. You can stroll through the high-end shopping street, which we did and then go into the water, what we also did.
Airbnb dinner
The good thing about an Airbnb is, that you can cook your own stuff, because you can use the kitchen. So after buying the ingredients, we cooked a chicken in honey-mustard creamsauce.