Ask your accountant to read Regs 1.469 and CCA Memo 202151005.You can have Nonpassive Schedule Es under certain circumstances but it appears he is listing it as passive, therefore creating suspended losses.Here is a previous thread: https://www.biggerpockets.com/forums/530/topics/1056436-clearing-up-confusion-on-tax-treatment-of-short-term-rentals

These entities do not appear to be set up as self-sustaining independent businesses. 

Your cellar appears to have potential based on its features like full-size windows and a separate entrance.You're on the right track!

So, would you rather figure this out on the fly what appears to be a one-off transaction? 

These appear to usually be bundled with security deposit replacement coverage.As for surviving the pandemic, MANY didn't.

So even elements that don’t appear damaged can be contaminated.

It's just a standard lease agreement from Avail.com (which appears to be the same form from AOA), with minimal tweaks from an attorney. 

On a cursory review, it appears that your cost of debt exceeds your capitalization rate, suggesting negative cash flow.

Which appears you have already done.

We also need to confirm the build style but appears to be a log cabin.