Remodeled a house before that had several animals as pets in the house (dogs and cats both) the animals were not let outside to use the bathroom (from what it looked like ever) we sanded down the hardwood filled a pump up sprayer with the odorxit (super contracted stuff mix as stated in bottle) sprayed all of the floors till they were soaked with it then opened the windows to let it all air dry.

But now my market has dried up and there’s only very expensive single family homes for sale that don’t work as rental properties because they have a negative monthly cash flow of starting at -$400 and getting worse from there.

Contractor brought up the important point that just covering it up with cement board and trimming out remaining upper 2’ section means that condensation from cold weather outside that would naturally form on the inside of the covered up window section would just run down to the bottom ledge inside the covered up area, and even if the ledge is waterproofed, the water from condensation will just sit there for extended periods since there would be no airflow to dry it properly.

I think the DSCR route would be my option due to high DRI. 

Not saying don't look for data, but I am saying, it's more in the comparison of successful properties, not in the cold dry numbers.

Resident went into crawl space and says it is dry and does not see mold.

Regardless they are on the hook for the lease its pretty cut and dry. 

Seems cut and dry, right?

It’s nice to see 4-5 guys fly in at 6am and walk in to a finished house with dry paint by 3-4pm.

These rubber seals dry out over time and crack causing leaks.