[fred cook]

I would put it inside the single space door if it will fit. Most lifts will require 11-12 feet of space from outside of post to outside of post. If you put it inside the 16 foot door, you probably will not be able to get two cars in that side. Of course, you could put one car up on the lift and park a second one beneath it. Putting the lift inside the small door will let you park 4 cars in a 3 car garage!