They hook up an air compressor and charge the system up and see if it holds pressure.

My inspector told me the HVAC compressor on the condo unit I was purchasing   wouldn't  make it thru the summer, so I purchased the warranty at closing.

Lucky it wasn't a compressor, right? 

(blown compressor)... first the repair had to be approved by the warranty company... that took several days.  

The AC blew cool and the heat worked, but the breaker to the compressor was tripped(we didn't know at the time).

.)- No HVAC/HEAT - units/compressors taken by previous owners.- Full cosmetic rehab including flooring- Roof Replacement- Septic Backup- Small Kitchen Fire (Appears to just be stove and hood)What options to do have to buy this home?

.$1500, you run a few feet of conduit to the compressors from the main and you're done. (2) 20A Circuits.

Benches out I've moved an entire small kitchen of cabinets, a 60 gal compressor with two 30 gal hot water heaters, and other sizeable loads.

If tenants balk or complain, I remind them that when the HVAC goes out and a new compressor costs $700, I pay $650 and they pay $50.  

If I was managing the properties myself and had the time required, it would certainly be somewhat cost effective (ignoring the cost of time), for me to replace stove coils, fix a compressor on a fridge, etc.