Bay area is beautiful and has great weather,so some will always be attracted, but as we are seeing in Manhattan for example, people are willing to consider alternatives.

LVT has scratch resistant finishes and are more common in heavy traffic area and are easier to replace should damage occur.

I think the critical piece is having a good team (cleaners, handyman, plumber, etc) in place with people you trust and having processes in place (process for turnover, process for safety checks, process for updating rental calendars, process for updating rental calendar based on future holidays and other important events happening, etc.To answer your question about the biggest risk, I think the biggest risk is the weather. 

At my own initiative, I bought an AC unit for their side of the property in June (15 minutes to order it + installation) and at their response to one of my inquiries, they suggested a weather strip on their kitchen door to keep the snow out.

All weather dependent of course.This is defiantly the more expensive and time consuming route to go in terms of STR.

I realize a lot of investors resist working with agents to avoid paying a commission when you buy. 

For slowness and thoroughness and change resistance - my money's on the Guvmmnt!.   

If you have a healthy cash stash for each property, you can weather down turns and unexpected events more easily regardless of how leveraged you are.

Memphis gets about 6 weeks of 20 degree weather, so I am hoping the LG models with high enough BTU will do the trick.

@Dawn Anastasi are landlords generally responsive to these questions or at times have they given you any resistance to answer them?