They have a dog in their unit without any deposit or any paperwork that proves it is a service animal.

Following BRAC has proved helpful to my brokerage business (commercial).

Deals are tough all over right now because of supply shortage and high demand (Millennials saving up for down payments during COVID, people moving out of cities, etc).

Worst Case: You may be stuck with 12-24 months of cash tied up until you can prove the appraiser's numbers were off and a new appraisal is warranted. 

And then investors who get portfolio loans on SFR's and really dont understand how tough those are to manage with reporting  and covenants in the loan that have to be met on an annual basis  they just sucked in on the low interest rate.   

At least with a 30-day notice, there's nothing to prove, no issue or hassle.

It is only a month but you can follow abandonment rules for your area as well, meaning if you can prove it was abandoned you can take it over. 

But it's a tough market right now.

I would ask the lender for clarification on why you need to prove need.

Might be tough to find that money for a down payment, but it makes the property perform better in the long run.The other option is seller financing, which is hard to find in today’s market, but a good option if you can find it.