I am interested in buying a long-term turnkey property in a nice area (I live in San Diego so this property would have to be out of state).

Ive owned a 3 family in Fitchburg MA for 4 years that has done exceptionally well with it, living for free in one unit for a while and constantly upgrading the property over the years.

Literally to save their lives.

I happen to live in AZ in the winter and MI in the summer. 

I live about 20-25 minutes away in Bloomfield Township (Lake Geneva mailing address) and have a rental in Delavan. 

Quote from @Braeden Warg: Thank you for the clarification and information.I live in Cabarrus County and have experience in residential and commercial construction.

Homes are affordable and we're seeing homebuyers enter the market with a lot of assistance available from the city.I’ve been investing in Detroit since 2019 while living in California and own 12 doors.

He's lived in Japan a few years as well (Fukuoka, I believe).

If they do, you may have a chance under the scenario you're proposing - if they share your concern for it's condition (although that seems unlikely since they've been living with it the way it is for some time, it seems).If you own it, it's pretty lowbrow to expect a neighbor to invest in your property. 

I'm imagining something more like add a wall, turn a bedroom into a kitchen-living on one side and a formal dining room into a bedroom on the other side, maybe add a half bath in each unit.