I prefer no padding under vinyl plank flooring, but some people will put a very think pad/vapor barrier underneath

The current problem really wasn’t a fault of his, just a consequence of the soil.  

Both of the neighboring houses have these as well so perhaps it's the soil?

This ”multiplying the acreage in each soil group and farm woodland by the applicable agricultural assessment value.

Inspector came back and said that my house needs some attention underneath and that it needs to be done before selling. 

I'd look for deals in the suburbs South of there and be aware of clay soil and foundation issues.

-Costs of street development and utility extensions (public water and septic)-Approval process for subdividing, what should I make contract contingent on to protect myself (approvals, soil tests, stormwater etc)-Is there a form of financing people generally use?

This time, I record the dampness over video, and also discover what appears to be black mold that I can see underneath the cracks of the floorboard.

And drying and treating the wood underneath.

He recently started his small business for deliveries (i.e. mulch, soil,  sand, gravel, caliche, etc.) and lawn service.