He's a tradesman by profession so I, and many others in the area trust his work and he knows soil grading and the electrical code like the back of his hand.

Prior Knowledge Unbeknownst to both Easton and the seller's agents, the Strassburgers knew that there were serious soil issues affecting the property.

And also If the soils are bad, FIX THE SEWER LINE.

Luckily sandy soil.This is an example, for discussion only.A.

Sometimes it can be as simple as downspouts on rain gutters that need to go another direction.Or a load of top soil places against a side of the house to make drainage go away from the house.If your agent does not figure it out  ( to make you feel better about the water).Then talk to their Broker this morning. 

Quote from @Sandy Gabin: I highly agree with Matt Devincenzo on this one.

I'd demo similar to a pool demo, bust up the sides and bottom, collapse the debris in along with some clean granular fill and then cover with additional soil as needed.

In your case, that seems to be the abrupt falling/caving, loss of structural integrity, or subsidence (shifting and settling of the soil, earth movement, etc.). 

If you are fine waiting and it is in a smaller area, try removing the sod and soil yourself. 

The house is leaning on one side due to soil settlement.