Four post lifts seem to be the overwhelming choice for home hobbyists. Frankly, I don't understand why. four post lifts are EXTREMELY limited in their usage.
If you ONLY need the lift for storage or VERY limited repair work such as the occasional oil change, then a 4 post may be the way to go for you.
also, for the novice, a four post does offer the simplicity of "drive on and lift" capability, while a two post requres locating the arms in a safe location. this makes a four post "faster"
(by about 30 seconds) to get a car in the air. I would think that this would only come into play if you literally used your lift for daily parking duties. If you don't feel comfortable setting the arms of a lift, then you have no business being under a car that is on one, and so you wouldn't need or want the advantages that two post lifts offer.
I haven't priced them,
(because I think that aside from straight up storage they are practically useless), but I assume that 4 post lifts must be cheaper to purchase, adding to their popularity.
From a repair or service standpoint, the only advantage that a four post has over a two post would be in the rare occasion that you NEED to work on a car with the suspension loaded. examples might be, welding in subframe connectors, or trying to locate a noise or problem in the suspension or driveline that can only be duplicated with a vehicle on all four wheels.
Other than the few points listed above, a two post will do everything a four post lift will, and MUCH more.
providing you have adequate ceiling height for an appropriately sized two post lift, you can easily perform car over car storage.
a two post lift has a smaller "footprint" in your garage floor, meaning it takes up far less valuable floor space. some folks will argue that a four post lift can be moved around on casters if needed
(providing you have another space to move it to). I would argue that ANY lift including four post should be securely mounted to the floor for safety reasons.
a two post offers unobstructed access to the underbody of the vehicle from front to rear and side to side.
a two post lift allows you to quickly and easily remove wheels and tires for rotations, brake repairs, and many other more complicated repairs.
I'll be installing a Rotary SPOA10 EH1 in my garage. it's a two post asymetrical 10,000lb capacity lift with extended height allowing me to lift taller vans and trucks high enough to walk under and work on.
If I had unlimited funds, I'd be getting a Rotary IN GROUND smart lift. these offer the advantages of a two post lift, but when in the lowered position take up basically ZERO shop space. Unfortunately, they probably cost between 10k to $15k installed and also do not allow for over/under parking. Unless the "under" car is extremely narrow
(or a motorcycle)!
just my .02
good luck.
P.S. IMHO, rotary is the best lift available, very expensive, but THE top of the line lift. stay away from the chinese imports. supposedly eagle and bend pak
(which is IMHO a terrible name for an american company. I was sure they were Chinese made imports judging by the name alone) are pretty good and there's another good lift whose name currently escapes me, but I don't have first hand experience with any of them.