We had metal cans in the yard because those lids were the best for staying fastened and keeping rodents out.  

For example; various real estate investments like notes or even real estate itself, precious metals, cryptocurrency, oil/gas, etc.

Lots of remolding and my other typical improvements like separate water so tenants pay all utilities.I've done many improvements including replacing the back deck the front porch a new metal roof in 2022 and a complete remodel of the upstairs unit in 2021.

I never knew a crack in a piece of metal inside the furnace would be such a safety concern.

Roof is metal siding is good but could use fresh paint.

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.  

Ask an HVAC guy what he's paying for sheet metal.

If a home has knob and tube and you are still finding ground wires.. that wire is going to a metal drain for the house.

@Joe KatoMany new gas boilers don't have domestic coils, therefore you can shut down the boiler in the non-heating months and just run the gas hot water heater.We've done both oil to gas conversions as well as hot water to hot air.

You can always spot them: there have a metal back with no exterior wire grid or tubing and some cardboard peeking out the bottom, where the compressor is.