So if you have to go remote (because you live in one of those markets) spend some time in your target city, plan on being there often, video call the contractors every day.

Is there a potential issue if the original tenant decides to move out and leave the other adult behind?

3 I keep seeing these "AirBnB is Dead" youtube videos.

Many YouTube videos and books on the subject will help, too.I found that practicing analyzing deals was very beneficial. 

For both tenant and landlord peace of mind, the property had an extensive video surveillance and security DVR system already installed by the prior owner, which covers outdoor areas and indoor common areas and records 24/7/365, as well as sensors for excess dB noise levels.

I read a few of the posts and would recommend talking with a lender in regards to the multi unit property since so far you have only watched videos on YouTube or podcasts.

You have to find the right strategy that fits your options...listen to everyone and verify what you hear because everyone will have their own opinion...Most of the west is more expensive than the Midwest and Mideast of the country...You might want to visit the areas and interview your potential team in person or trust what you are shown through videos of the areas or ... sometimes you can make a killing on an area that everyone thinks is unsafe and you find a that is very safe and cheaper than it should be, because it is near unsafe area or people think it is unsafe.

Check out the "Enemy Method "You can find videos.

This would ideally include a video doorbell with an app that can manage both and see the cameras/recordings for both systems. 

Maybe make equity sharing an option that offers a lower upfront fee.Reference: (You may have read it already but if you haven’t I would recommend checking out Dan Sullivan’s videos/media).