Hello Doug, I am not a real estate attorney nor is this legal advice.Unless someone's state has specific laws banning contract assignments you should be fine doing the following.  

Happy to share more specific ideas!

What's the best way to navigate this situation regarding the application process as well as the lease administration?

When we got engaged, my wife didn't want roommates but was willing to do a two unit situation.2.

Most do a LLC but again it can be very different - for example I have a C corporation, had a S corp, had a LLC etc. and each one for very unique and different situations. 

Happy to keep the conversation going if anyone wants to dive deeper into trends or specifics!

Specifically I think a lot about the smells that travel through the duct work between the units.

NYC apartments will have a different car requirement from Orlando, but he used that methodology in this specific small city and was an investor from the 1980s-2000s, so a lot has changed, but I believe there is still some truth to it.

I think with it being newer accounts/investors they don't think of the specifics needed.

Saw a similar situation with friends.