Portable AC/Heat units in rental property

[Donald Francis Reese Jr.]

I have a small 900-1000 square foot home In Columbus GA. Avg winter temp gets around 37-40 degrees The gas heater is shot and the ductwork is torn (located  in tiny crawl space) I already know cats did it. Central air was never installed. I’m getting costs to add central air and or mini splits from 10-13k plus another 1-2k to upgrade electrical service. The area rents anywhere from 450-700 and majority of houses have window units with gas heaters so tenants would be accustomed to the setup. My only concern is how well the ac/heater units heat- would a couple of these units suffice for heat in a room? Has anyone had any experience with these before with heart their rentals or home even? 

I own the home free and clear and do plan on financing to install a ac unit. For one I have other obligations for this year. Really looking for a quick fix without spending tons of money.