Then they rely less on the refrigerant and more on the heat of friction from the compressor which ='s a shorter life span on condenser motor. 

I've wanted an air compressor for a long time, but honestly don't know what I'd use it for.  

Although, are you talking about 2 full systems for $13k ($6500 each is high but not really high) or one compressor with 2 output units? 

It also doesn't need much, but could use at least one new AC Compressor and new windows.

Just as a point of reference, my LG fridge had a poorly designed compressor and when it broke they fixed it for free and covered lost food.

GE & Whirlpool will sometimes tell you 2 weeks to get a new compressor in bc they are backordered.

You can buy a very cheap  HVLP sprayer at Harbor Freight if you have a compressor. 

99% sure it's one of the following:Roof leaking into foundation seeping to the bottom of houseDownspout overflow or spillage seeping to bottom of houseSumppump back up or not workingAir compressor leak from HVAC unit if central airClogged sewer line (if toilets are having difficulty flushing)Water forming a reservoire outside due to unsloped ground (need to have a downslope from house to keep water flowing away from foundation)*Next door unit experiencing one of the above

Naturally its the compressor . 

Now each unit has it's own electrical panel, HVAC, range, refrigerator, dishwasher etc...but those are unit owner responsibility if they are inside, and if they are outside (like an AC compressor) they are limited common elements and are excluded from HOA coverage.