Too, if the unit ever gets low on refrigerant, the lines will condense water and drip, possibly causing mildew/mold.If you do add central AC to a Class C unit, the value of the property won't increase and you likely won't get much, if any, added rent.  

Could be leakage, clogged, dirty filters, and electrical (not triggering the condenser hence the refrigerant isn't empty) as well, but inspection should've picked that up.

I had a tenant bring in a large dog that peed on the air conditioner outside and peed a large hole through the condenser.

I have seen a few central AC outside condenser units to be missing with lines cut.

If your not a real estate agent with access to the MLS this might be a good tool for you as it condenses the information into one website, however websites like zillow do it for free.4.)

If your interested I made a summary of it to condense it a bit and give some insight.

By the way the equipment (furnace, coil, condenser) will cost YOU somewhere around $1800 - $2400 depending on the house size.It will cost one of these shops far less than that, but of course, they will when asked say it's $3000 + worth of equipment.  

There would be one or two air handlers and condensers.  

I don't focus as much on crime because criminals have cars to and drive to the good areas to steal ac condensers also. 

No condensation, a genuine question as many don't actually know.