Seeking wisdom from those who have installed a lift

Well ****. I was at the shop earlier and the landlord stopped by. He said he found the paperwork on the slab and that it was a 4" slab. We talked and he agreed to let me cut the slab to pour a thicker footprint where the lift will go. I guess it's good to know these things now rather than later, when the installer shows up to drill the concrete....