He gave a handwritten, scribbled notice saying he was leaving by the end of the month.

I never receive any redemption notification or other notices regarding the sale of the tax deed. 

Pamela, generally if you're on a month to month, you only need to give the amount of notice required by law in your state. 

I noticed you mentioned If you plan to retire somewhere else , you could sell and do a 1031 exchange for that property.

Provide proper notice of non-renewal near the end of the lease term and then sell when they move out.

If not, what I would do / have done is take the letter to the tenant directly after close, explain that this is now your debt, and offer to waive it if they sign over the property ASAP (according to whatever notice you have to give). 

We’re you sent a notice that your mortgage was sold to a new lender?

Thus, as a result the tenant was given notice to vacate at the end of their lease per landlords request.

I noticed a pattern when paying my taxes the last two years and it seems like I’m paying state income tax in two states from long term capital gains of stock sales.I live in CA (since 2013) and have a rental property in CO (purchased in 2011).

I would absolutely prepare for a significant jump as it will assuredly happen with your 2022 Notice of Appraised Value.