i can give you short answers for 1 and 3...

1.) i keep my trainer in the bathroom on the sink. i know its not the best locale but it works for now since we live in a small apartment with 4 cats. perhaps you could hang it from the ceiling or something?

3.) if you already have a trainer, then a good low wing plane would be my suggestion for a second plane. my choice is the world models t-34. i've read great reviews on this plane and everyone seems to like it. Plus, its an ARF if thats what you are looking for. for a kit, i would suggest a sig 4-star 40 or 60.

Hope this helps and keep in mind.. i'm no expert by any means.

John