I was wondering if that would work but have not used them enough to speak wisely.Its gonna suck and his grass is toast regardless, but a skid of 3/4" osb or plywood, or some 4x4 swamp mats is about your only option. Plywood could be muscled around as you move the lift. Mats would likely require a mini-ex or tracked skid steer to move.
Just need to spread the tire loads out to help minimize sinking.
That or hang off the roof.
Should work for no more than you're gonna be doing. Mats will sink less but will be more cumbersome, plywood will bow and may crack, but if you double it up and do about a half sheet overlap, you should be ok. Client just needs know the yard is gonna look effin awesome til it drys up some. It will be a bit tedious to move the boards around if you don't get enough to do it all at once, but if the long wall doesn't get one in the middle, you could make a path across the short wall side and work the back corner from the lift on that corner, then just work the other end from more the parking lot on that end.I was wondering if that would work but have not used them enough to speak wisely.