An estoppel certificate establishes the current status of the lease terms for a third party.

Just because the lease says no pets, the tenants now gets a certificate his dog is now a service dog and they get to stay.

It's not uncommon in hot growing area where houses taking a long time to build for a builder and when the new home buyer put a new construction under contract, once the house is built, the market has appreciated a lot and you sold the house right after certificate of completion and enjoy all the appreciation accumulated during the construction period.Another story for you but on the losing side: before 2008, the market is hot.

Biggest bit of info I learned that saved a deal for me when I purchased a property in an A/E Flood Zone which had no certificate of occupancy was to immediately have the property reassessed.  

But it's a steady way to kick-start your portfolio with no/low down payment.Your VA Loan Certificate of Eligibility (COE) is the definitive way to determine if you have remaining VA loan entitlement.

Once you get rid of him, then do your research.HUD guide: https://www.hud.gov/sites/dfiles/PA/documents/HUDAsstAnimalN...HUD is clear that they can't use online certificates or "registries" to claim support animals.

More:"for rentals that are 28 consecutive days or less they are considered short term rentals, which require a Vacation Rental Registration Certificate and TOT permit.

Normally I wouldn’t be concerned but I’m using a new lender and they asked about getting a certificate of occupancy today during the underwriting call.  

If it's a new conversion, you'll need an inspection by the city to verify these things to get a Certificate of Occupancy, which is required for your rental license.

Any certifications or warranties that you have on the house, keep that handy too.