2 Post Lift - I finally installed one in my garage!
 

This is something I have wanted for a long time. This particular lift is offered through Costco and has some features which make it perfect for a normal residential garage. The posts are easily movable for storage out of the way as they have wheels(you tilt them back and roll them like a two wheeled dolly). As you can see in the pictures below, I store one post against the back wall of my garage when not in use to free up garage space. The hydraulic power unit is portable and plugs into a 110v standard service wall socket. The lift supports up to 6000 lbs. and raises the vehicle about 50 inches. At full height my S4's roof clears the open garage door by a few inches. This setup makes working on my car a lot easier and safer than floor jacks and laying on the floor. Now I need a vintage car that needs more service than my S4.

With a base that small how is it not tipping towards the middle???

...its bolted to to ground, u can see the massive bolts in one of the photos

I love it, I might have to price this out and look into something like this. Being able to put it in the middle of the garage for easy work would be perfect to then be able to quickly unbolt it and store out of the way.

What did you use to sink the bolts into the slab with?

The lift comes with the proper anchor bolts and a sacrificial bolt to set them in the concrete. A friend of mine with a hammer drill put the holes in the concrete. The whole job only took about an hour. I think the slab needs to be 4 inches thick at a minimum and in good shape without cracks in the area of the bolts. Once in place, you use the supplied shims to align the posts to each other and make sure they are vertical. It now takes less them five minutes to set up one post to work on the car.