It was -20F and the highest affordable temperature was 58F.

It was totally below grade and the temperatures there were 10-20 degrees different from the floor above. 

Temperature control thermostats that have a max,  we use a  landlord stat from Chicago temperature control.

I've been working construction, welding, roofing, plumbing, etc. for 7 years now.

(Note to investor: I know you feel like your acting stupid as a real estate investor when you do that technique above, but what you are doing is raising the emotional temperature of the seller. 

Shop for a HP which will operate to below zero and use a thermostat which will lock out all resistance heating below a certain temperature - aim for a 0º change over temp.A HP will cost about 40% of the cost of straight electric.

Also you can use high temperature spray paint from home depot on them and it comes out nice, there are many colors to choose from, but I wouldn't even bother with that, just clean it up is what I suggest.

They are always pushing people to use the forums so I just wanted to get some feed back / advice and maybe get the temperature of local markets.A few more deets: I live in the San Antonio, Tx area and would like to invest locallyI would also like to use as little of my own cash as possible IF IT MAKES THE MOST SENSEI've worked in construction all my life and I know how/what to do to get things done.

I've always said that if it weren't for the seriously frigid temperatures I would've relocated to the Chicago area some time ago.

Maybe add a yurt or 2 in the nicer temperature months and....voila.....less grass to cut and more money coming in