I lived in a 2-story house all of my life until I bought a 1-story house last year. Generally, I really like a 1-story house and would prefer it for any future purchase; however, there are a few drawbacks.
Pros:
1) 1-story house is easier to get around
2) less wasted space on stairs,etc.
3) don’t have to worry about kids falling down the stairs
4) appeals to older/mobility challenged individuals
Cons:
1) I used to leave windows open on the 2nd story but that is much harder with a 1-story house
2) Someone could be standing right outside our bedroom window
One thing to be aware of is that our 1-story house is not completely level (the entry is slightly elevated) which would make it impossible to get around in a wheelchair. If this is the case for the house you are considering, you may not get as many mobility-challenged people interested in your house at resale.