I have yet to see a hands off ADU addition obtain a valuation to cost ratio anywhere close to approaching what you site ($210k cost to add $350k of value).  

Ours are close to 90% Airbnb...I theorize it is because of the unit type and fact that we are always on page 1.

I think the couple are playing games with me and will pay May's  as close to the end of the 30 days as possible and they basically will owe me again for another month for June.  

I do not want to ruin anyone's vacation plans for those already booked next week and we close Monday.

You maybe be able to live for free or pretty close to it, depending on how extreme you get with it...AND make some decent cash when you sell as well...especially on the 5 year plan vs 3.

There were 6 vacancies at closing, and we are in the process of remodeling those units.

I want something that’ll automatically lock as the door closes

You always want the city on your side (or as close to it as possible) to foreclose future issue and that starts with finding out the how on your own before bringing an expeditor to smooth the process.

In that case, i am capable of covering the 20% down payment and closing cost with the money i saved up.

I am planning on closing an investment property `all cash` under an LLC name.