Do you REALLY need to clean the fence line or power wash the house?

Remove everything that can not be cleaned, wash everything down with TSP and paint with Kilz.

We are allowed to leave it open, screen it with insect screen to form something like a screened-in room, or install breakaway walls that will blow or wash away with only 20 pounds of pressure but otherwise provide a weak, visually appealing enclosure. 

And the transition from the dirt/gravel alley to my driveway was partially washed away, creating a possibly hazard for a car (only small vehicles would be able to make the turn).

Who was to wash all of them...I would think a dishwasher would be nice....

The 1st level where they are living will have a lower amount of radon that is acceptable by EPA standards but they use the basement to wash clothes, which will have 2.5 times over EPA standard amount of radon.  

In one house there is already a washing machine in the basement, and I just don't want to bring it upstairs.

The entire underdeck area had to be bleached and pressure washed because the food left attracted animals, especially birds and mice, to come and crap on everything including all over our new outdoor furniture, fireplace, bar, and concrete area.

I got the feeling they are just ready to wash their hands of the whole property.

Reason he gave was he needed a favor as he's going on a business trip.