Only a few simple documents are required, including a valid passport, birth certificate, and proof of address.

Should i ask the downstairs tenant for the footage to have as proof to have and document for anything in the future? 

Airbnb has never penalized bookings when the property is sold in my experience, just to provide documentation it was sold.  

Once pre-approved, gather your financial documents like pay stubs, tax returns, and bank statements.

If they say "No" then ask them to support that with documentation to avoid a boiler plate response. 

That’ll be $50.”Document EVERYTHINGLiving with tenants means you see it all—good, bad, and downright ridiculous.

What documents do they require, what credit scores do they allow, how do they verify previous rental history, etc.?

The sooner you regain control, prove that you fully intend to enforce the terms of your lease, and that you will not be 'played' by their recall of events or documents, the more effective this action will be.  

Your goals will define the route you take on this but building a list for buyers/investors is a time-intensive activity and the list is a living and breathing document.

CPAs often advise against pursuing this designation unless the time commitment and documentation are robust, as failing to qualify can result in IRS audits or penalties.The 500-hour rule pertains to material participation in specific real estate activities or businesses.