We were told that the previous tech exposed our new furnace (less than 2-year-old) and there could be rusting in the heater exchanger, which would cause the furnace to fail as well in the near future.

In fact it's a perfectly rational strategy from their standpoint and one that now needs to be exposed by those that will have to pay the price.

I would recommend any future investor do their best to get exposed to construction even if it's cleaning up a job site (for free or minimum wage) for a few hours each week.

It’s scary for me to think about bringing other people in considering the boundless reports of less than ethical business dealings some are exposed to.

There's no extra CA punishment for that, but you and your properties are potentially exposed to legal risks, so you might lose the properties if things go wrong.

This could be due to the uncertainty of where to go or the associated risks with moving and becoming more exposed to the virus.

Being on Bigger Pockets as well as joining facebook groups will help expose you to a number of off market deals and the wholesalers who can help to supply such deals.

If the mobile home has a propane tank or oil tank for heating, it can be problematic because tenants may not be able to afford to fill up and use other types of heat sources.

If all your properties are in the same place, they're exposed to the same risks.

Are they doing everything they can to expose properties to the widest possible market?