4 post lift vs. 2 post lift. Pros and Cons.

I made sure there's a foot of concrete under each column of each lift.
I wouldn’t trust under 6-8” on a four post, and 10-12” on a 2 post. Where the post aren’t involved 4-6” would probably suffice.
Concrete needs to be reinforced.
The main thing to make sure of is the condition of the cables, or chains as my big lift uses, and to insure the safety locks engage, and work properly.
I’m constantly doing other businesses and dealerships work, as they don’t have the lifts to accommodate the weight or length of the jobs I do, so safety is paramount.
Never cut corners on a lift or the installation.