I've said it before, and it bears repeating: I love living on one floor. One of the things that I really enjoy about our apartment is that although there are quite a few steps until I get in, once I'm home, there is no more shlepping up and down.
When I spend a couple of days in a place where there are stairs (okay, my parents' house is probably the only frequent example) I get so winded going up and down within the home. Yes, getting into our apartment involves a set of 8-9 steps leading to a path, another 7-8 stairs leading to our front door, and then about 13-14 steps leading upstairs. But once that gate is closed, that's it. Bedrooms, bathroom, living/dining rooms, kitchen, washing machine, dryer - it's all there on ONE level. And I love it.
Until I was five, we lived in Israel, on a first-floor apartment in Givatayim. Since then, we lived in houses in Queens - but being that by then, I, the youngest, was old enough to shlep my own self and stuff up and down, it was more feasible. Not as easy for my mom I'm sure, with the laundry area being two steep flights away from where the clothing drawers are. I'm wary of the shlep-mania involved in having babies/young kids while living with internal steps (Mountains of laundry! Infant car seats! Etc.!)
I suppose I'd get used to it the way I'm accustomed to the mountain climb involved in getting groceries into the apartment and getting a double stroller up and down the narrow, steep stair jungle. Somehow I'm in shape enough to accomplish those tasks fairly often. Now that Andy's climbing the steps with help, it does take a literal load off.
As long as there's enough space (and what a subjective concept that is!) I don't believe that there's anything detrimental to kids about growing up in an apartment. In other countries where my husband and I have lived (Russia, Belgium, Israel), apartments are almost always the standard for families through the years. I don't really believe that kids suffer for it or grow up feeling boxed in.
For as long as I can, I prefer to keep it flat. Happy ranching!