An appraiser likely won't be able to value a 1-4 unit property based off STR rents (whether projected or actually incurred), and if they are, the lender won't lend off said valuation for their applicable value (value they're lending off of). 

To receive the 4% ratio, you have to submit an application showing the property is your primary residence.

If you receive a loan application that reads: How many flips have you completed in the last xyz years?

or scammed them on their application fee (like we're going to make a ton of money off those).

Supported by assorted support services related to disaster relief for those applicable parts.

However, it's important to note that this is only applicable within the city limits.

Review the quality of the tenant base (do they have a history of paying on time, what were the original screening criteria, do they have applications on file).

(Do you really want an applicant who can and wants to move in tomorrow?

Is your DSCR ratio greater than 1-meaning are you cash flowing (according to the lender's criteria of mortgage, property taxes and insurance (and HOA) if applicable).

Because FF is not a booking platform, make sure you follow all applicable fair housing laws when talking to potential residents.5.