My suggestion is to find the right mutually beneficial partner that could help enhance you short term situation and reach your long term goals faster.

A waterproof textured laminate is nice in common areas, and carpet bedrooms.

This keeps the uniform look, if you concrete on top of it you won't match the color and texture!

:If I had to pick one thing, I'd say flooring - specifically a hardwood-type flooring, including the bedrooms.Hey Sue, I figured flooring would be one of the top just because it is something all rehab's will enhance or replace.

Not sure what the cost per square foot would be by the time you got all the texture, paint etc. done.Maybe worth looking into.https://youtu.be/GLjhrXFo0Kw

It is a big investment, but you will have improved the property greatly, and enhanced it's value.And, ask him to do a cooling and heating load calculation to determine what size equipment you need. 

After you see they a good tenant then gradually increase rent, also a few cosmetic enhancements can go along way in justifying the rent increase and their preception of the increase. 

Which included demoing the back porch, new HVAC, new electrical, re-sheet rock with tape texture and paint, kitchen island and counters. 

@Martin Lopez  A warm welcome to BP Community - a place to enhance and share your REI knowledge.

In order to help alleviate these difficulties, and to enhance his/her ability to live independently and to fully use and enjoy the dwelling unit you own and/or administer, I am prescribing an emotional support animal that will assist [FIRST NAME] in coping with his/her disability.I am familiar with the voluminous professional literature concerning the therapeutic benefits of assistance animals for people with disabilities such as that experienced by [FIRST NAME].