I looked at a 30'x40'10' I don't ever plan on owning a dump truck, backhoe or a camper (we never go camping). So I think 10' will be high enough, I was planning on putting 3 garage doors 9x8 in it. It was an QSI built building by the Amish. Built with a 6/12 pitch roof, 2 windows, walk in entry door, 3 garage doors, Microfoil insulation,, wainscoting and concrete floor they wanted $23,000!!! I thought that was pretty expensive. I have no idea if that is a good price or not. I wouldn't mind having it a 30'x50'x10' but I don't know if I could afford that but I don't want to be like 5 years from now saying dang I wish I would have built it bigger.