Are you sure the occupants haven't poured cement or acid down the drains?

I wouldn't say the vinyl laminate is cheap, we are paying $2.34/ft and that's me installing it.I could get laminate down for $0.92/ft.Tile down $1.70 ft, with grout, cement board, nails, etc.Carpet w/ 8# pad installed by others for $ 1.12/ft

Keep the tree and use the cement for the driveway.

They all say the main cost driver is the labor to break up the pool and cement and just filling it with dirt as-is isn't an option.

Just watch the water to cement ratio as too much water will dilute the strength of the concrete and continue to hydrate longer.

I used to know someone who did this quite successfully, again you would have up front costs of cement pads, water, sewer, and electric, but given how many trailer parks are around it seems like a valid investment.

Caulk the wall; cement the wall; or dig the outer foundation, seal it with a membrane, tar it, then fill back in the dirt?

If so just go with an upscale vinyl or factory painted cement board siding but again I would say color depends if you're keeping the roof that color.

No real need to prove they're the ones who poured cement down the drains. 

In this case, there was some old cement paint on the driveway, and they wanted the whole driveway and building scraped of not just peeling paint, but any paint that COULD peel.