Don't do it, with the affordability of lifts either 4 or 2 post it just isn't worth it. Fumes, Fire, trapped by car etc they really are very dangerous.
Agreed, not worth the effort.
You end up with a hole in the floor, that you must keep covered with something strong enough it won't break through.
You are down there in the pit working, and damn-it, you forgot your widget tool. Climb up and get it. Oops, forgot the thing-da-ma-jig tool, climb up and get it. Bang, hit head on bumper climbing up for the what-ch-call-it tool. Trip to doctor causes you to loose your train of thought. You forgot were you were. A week later you can't find the who's-e-gotchi tool, because your short term memory was wiped when you hit your head. You back the car out because you are pissed, but after you get it, realize it won't start. So you push... Your foot slips on the floor, and you fall into the pit, breaking your leg, but fortunately you do find your tool. Only too late you realize your cell phone doesn't work in the pit. Your wife finds your body about a week later, and hopes you didn't suffer much. The medical examiner thinks you had a rough time of it, since your fingers were worn down to the first knuckle. Oh, well, there are worse ways to go, right?
Then there is the issue of 'drainage'. You cannot have a drain in a pit. You end up with a 'sump' which you must either scoop out, or pump out. Of course that pit in a pit is where your broken leg went, and you could not get it out. Oh, well, at least the water in the sump numbed the leg so you didn't feel the gangrene as much.
As a final note, your widow did have the pit filled in (with whatever tools you had left down there still there...) and now uses a nice 2 post Rotary lift.
Cost of framing the pit: $400
Cost of pit's re-bar: $120
Cost of additional concrete: $375
Cost of cover: $350
Cost of pump to pump out fluids: $280
Cost to fill in pit after death: $400
Sure there was a cost savings! Total of the sump was only just under $2K, but when you add in the salvage value of the lift, the lift is much cheaper!
(Yes, I considered a pit, and just the fact that I'd have to climb out to get each tool needed was enough to convince me that it was a non-viable project.)
