How many floors do you put into most of your home builds?

I'm horrible. I like my sims to basically have everything I have in the game. But, I have to admit, that it is less hectic when I play a one story house. When I played the Sims3, I almost always used 64x64 with at least two floors and a basement and they had all the store and all the rest too. It took a huge house for it all. :)