central air or wall unit

[Maria Car]

My rental unit has a 500 cash flow each month , the central air fan motor went out , eventually I may need to replace the entire unit a/c and furnace which is about 3 k, the house also has a swamp cooler , edison installed the unit for 80 dollars and it cools about 1200 sq feet , the bill is only 25 dollars per month using the swamp cooler it was put on a window compare to 300 dollars for the central air. The house is only 930 sq feet . I was considering installing ac unit on the wall with of course the back of it being outside through the wall.(like the one's you put through a window) I was thinking of doing this because the cost of ac will only be 500 versus the central ac costing 3k and it will cool 1200 sq feet .. plus it only uses 1200 watts versus 3500 watts on a central a/c and I do plan on keeping the house for at least 5 years or more, maybe when i sell it I can install a new central air or ductless system. The reason I am considering doing this is because #1 the house has a swamp cooler and the bill is cheap eah month 2) the ac for the wall is only (500) dollars will only be used july and aug 3) the maintenance 0 compared to central air.5) the house is for low income but never the less I have nice tile on the floor .laminate , granite counter tops., oh and new windows and fresh exterior paint. The question is: central ac now?? or when I sell it , and just put a 22000btu wall unit , and the added bonus it has a swamp cooler now, giving the tenants options to use either one. thanks your advice is appreciated.