I have to agree with the others, 10ft, you can put a 2 post lift, my brother has 122" finished ceiling in his garage he has a forward 9K lb 2 post in there, floor plate, he had a friend of ours come in and cut the floor so it is recessed, cost him $150, so the floor plate is level with the floor, he also installed a switch on the ceiling in the center of the lift going front to back with a wire, when the wire is pulled it shuts the lift down before you can send it through the roof... Pretty simple design he came up with, I was making it much more complicated, he figured how to do with with the switch and insulated cable, he can gt it 1/2" off the ceiling and it stops, he actually uses it as a stop, lol just holds it until it stops, I think he trusts that switch a bit too much, but so far so good... He can lift his vette so he can pretty much walk under it...
1 note if he recessed the floor another tiny bit he would not be able to lower the lift all the way with out them touching the floor, but it makes getting the arms under a lower vehicle even easier...
So for the same money I would go with a "real" lift...