We're trying to decide on what material to use to replace it.There's not great air flow to inside which is why we're considering moving away from carpet and something that may hold less moisture, easier to clean, look more modern etc.

Is it green or clean?

Make sure they are capabile of cleaning up and getting a bank mortgage.  

Yeah your idea seems right, but he should probably give her her two months rent back if he wants out clean.

Rehabbed property cosmetically -- cleaning, painting, new fences, garage doors, lighting, faucets, A/C units, appliances and landscaping.

It's just a matter of removing the old mortar material, cleaning out the opening, and then applying new mortar in the space.

I’ve found HD laminate with white subway tile backsplash looks great is easy to clean & affordable

I did have the building painted - and made sure it was cleaned up.

I keep hearing bits and pieces about a rental strategy that is best called "Renting to the Disabled by the Room for Above Market Rent" that goes something like this: (1) Buy a house with as many legal bedrooms as you can that still has a decent sized common area, (2) rent it out to the relatively high functioning disabled crowd, (3) via some [unnamed] Government program the State pays above market rents for each of the tenets. (4) Send a house keeper 1-2 times per week to ensure the place stays clean and otherwise make sure there are no issues.The up side is: you get above market rent with a much higher than average tenant count.

Regarding the high cost of the abatement process, my understanding is that it is mostly labor for the intense cleaning they need to do after the abatement.