I've been looking at these myself. I was looking at the 4 post variety. I thought they were a little more stable and spread the load out on 4 posts rather then two. Found a few companies that had the them for around $1900-2300. If I remember they were in the 7000 lb capacity range.
I was going to use it primarily for double storage,but also to work on the cars.
Ron

Do these post type lifts have to set into the concrete or do they fasten some other way to the floor?

The one a neighbor has is bolted to the concrete floor of the garage. His is a 4 post. He stores a Corvette on the upper tier.
Ron

I have installed a 2 post in ground hoist in my garage and my father has a 2 post above ground hoist in his. A above ground 2 post hoist at $5ooo in to much. As far as brands go, Rotary in my opinion are the best. They have been in bussiness scince th 1930's. I love my in ground hoist. You dont have to worry about door dings and trying to work on the inside of the vehicle when on the hoist. The above ground take up a lot of room also unless thats not a problem. You also need a tall cieling for a hoist to work properly.