houses- 1 or 2 story?

[2up]

I prefer 2 story with some bedrooms on the main floor and some upstairs. The only exception would be a 1 story with a floor plan that has some bedrooms in one area and the other (master) in another, seperated by the main rooms. I prefer to not have the guest and "kids" rooms near the master. I'd rather have the "kids"/guests be able to go to bed or do whatever without me having to be concerned with what I'm doing bugging them and vice versa. Ultimately though I really do prefer a 2 story.

ETA: In Arizona, much as in Vegas, basements are the exception not the rule. The ground here is too hard to dig into and there is some other reason I can't remember? I would actually like a basement though for the extra space, although I hate the dark/damp basements in the midwest/eastern states I've lived in. Walk out basements are a much better deal though because they allow for more light and a more moderate temp IMO. Oh, and, I love fireplaces. They can be used for a couple of months in the winter here in AZ. In my last house here there was a double-sided fireplace which opened to both the family room and the formal living room.