Brace yourself Celeste, I mixed up TWP/Olympic Honey Gold/Cabots 1100 al together out of some half empy cans and sprayed the whole thing, inside and out. It has a sand box under the steps, two sky lights, electricity, and a working traffic light. Kids grew tired of it in one summer, but I enjoy it.
I bet your kids tell all their friends how cool you are and how you are the best dad in the world. When their friends see that cool tree house, I bet their friends get very jealous.