The quick turnaround required precise coordination and efficient execution, highlighting the importance of strategic planning.

I am curious to see what steps do you have or requirements do you put in place to ensure you are securing the right tenant? 

There is another easy route that requires thick skin, invest in warzone cause you will here many investors don't do it and because of that house in those area cost $10k or less.

The accounting needs to satisfy the IRS requirement for record keeping in case you get audited.

...perhaps the lease could state that if the tenant exceeds that threshold, then they're required to get a storage unit? 

This process can be very costly, requires zoning permission, in addition to all the items you listed.

Insulate, add electrical, mini-split ac, and possibly plumbing, as desired, drywall, tape and paint, put built-in cab's on one side if you want, hang the tv, speakers, etc, install bi-fold/multi-fold doors on the side leading to a patio, and replace the garage door with an insulated one keeping the track and removing the motor, or install a carriage type garage door into the existing garage opening.

We provided her with all of the required records.

Did she ever mention requiring any noise buffering for her unit due to her sensitivity? 

Yes, they require some extra follow up.