Portable lifts are designed for that. A bolted lift probably isn't. Also, check your spec sheet for the lift, 5 inches of concrete sounds marginal.
I put an Ammco 12000 4 post in my shop, it called for 6 inches and specified no cut lines within a distance of each post. I asked the concrete guys to wait a couple days before doing cuts so I could mark the appropriate areas as no cut zones.
There were similar restrictions for my 2 post lifts with the biggest difference the distance to cuts. Much larger area for the posts.
Note, I was doing a commercial installation and things got used daily. For a hobbyist you might get away with less but things only have to go wrong once.
I recommend rethinking your lift purchase and getting a portable one
I agree, I am looking at a portable 4 post lift, probably the backyard Buddy, if the lift is not portable it should be bolted in, too much risk otherwise. I think 6” is the minimal concrete recommended, I have 16” 4000 psi on the thin side and 36” on the other so I haven’t studied the concrete requirements too close, figured I have enough.
