What costs you will NOT double: The plumbing fixtures, the water heater, the wiring/electric panel, amount of piping/PEX,  the condenser/furnace.

I see too many landlords trying to save their money fixing the junk these companies are putting out.Typical parts to fail: evaporator fan motor, condenser fan motor, control boards, icemaker, water valve, door switch, defrost sensors, defrost timers(some models), bi-metals, heating elements Recommended brands: Whirlpool/Ge/Maytag/KitchenaidProblem child’s Samsung/LG/Frigidaire/Electrolux 6.

Minor cosmetic repairs have to be made and there is a value add opportunity with the addition of a condenser for HVAC.

Then in July the same AC was having problems, and it turned out to be the condensation pan was leaking, which caused water damage to relays and other mysterious AC parts.

For the mini-split I was considering dual zone, but again, that would still require multiple installations even though there is only one condenser.

Now this is just a VERY condensed reason , which there a ton , on why you should or shouldn’t incorporate.

General cost for a Furnace and Condenser swap out?

The philosophies in that book are very similar to the BiggerPockets methodology condensed into one book.

The condenser in my outside AC unit was stolen (there is literally nothing inside the case).

The two most likely culprits: lack of bathroom ventilation or general window condensation during extremely cold temperatures.