With that being said, the current Covid-19 environment is very challenging for landlords trying to rent a vacant property while trying also to keep you and your family safe and healthy.Rent-o-meter as @Marshall M. suggested is a great tool for normal property types, but given the uniqueness of your property I would also recommend tapping into a locally established Property Management company in Napa that can give you more insight into 1) current demand given Covid-19, 2) historical demand for a generational living setup as you currently have and 3) expected rental income for the setup you have and the given amenities.As an owner and investor, there's no reason why you cannot continue to keep the property listed to catch the right buyer for your property, while at the same time placing it on the market to see if you can get a Tenant in at a price point you are comfortable with. 

I've had some incredible tenants that were inherited. 

You might be able to find an out of state notary to do a remote online notarization, but there is a lot of room for fraud, and your personal information isn't incredibly safe.

On the other hand, coastal cities are good for flips, sure, but it's incredibly hard to get anything to cash flow (at least with debt).

Our RAL homes are doing great because of exactly that...controlled, smaller environments (10 beds or less).

They will work out to good investments but compared to my MF holdings (about 1,100 units), they are incredibly more hands on and time intensive, and don't cash flow as well.

It’s a tough environment But with a good co-signer something should be possible.

I don't know anything about meth remediation, other than it is INCREDIBLY expensive, like you have to go down to the studs and do a full gut, so $40K is likely not your number, your number is likely $60-80K.. that's the one thing I will run immediately away from!

We realize this is an incredibly hard time to ask for a rent increase, but we don't see how we cannot as a business. 

We simply would not be able to service our debt.The danger with substantially increasing the money supply in an environment where you can’t increase interest rates is that you can potentially create a substantial amount of inflation.