Understanding that as compared to steady and predictable long term rental rates, STR rental income varies a lot month-to-month based on many factors: seasonal demand, competition, your standing on Airbnb or other platforms, your personal occupancy goals/philosophy (I.e., highest occupancy at lower daily rates, or Higher ADR with more infilled nights), personal usage blackout days, etc. 

Skylar, will you be an owner occupant? 

Property is protected by different types of Lease Restrictions according to zoning requirements - each subdivision is subject to both zoning requirements and developer deed restrictions - both of these can affect how long you can rent / lease a property for .There are some areas that have no restrictions at all and others that only permit owner occupancy and every variation in between really - you would check each property for their specific lease restrictions or get your Realtor to filter for it.

You will still need to depreciate the structure over 39 years but can accelerate the depreciation and take advantage of bonus depending on the year of purchase/occupancy. 

Not ready for occupancy yet.

Then analyze what the going rent rate is and see if it will cashflow with the units filled based on how much money you will need to put into it.For the house, that's fantastic that you want to let the current occupants rent to own it.

Graham,A few things to remember from an insurance perspective:1. once the Dwelling moves from owner occupancy to tenant occupancy the policy will most likely need to be moved from a Homeowners form to a Dwelling/Fire policy.   

What's the projected occupancy rate?

Occupancy date3.

And make sure to get a C of O (Certificate of Occupancy) if required in your jurisdiction.SIDE NOTE:The Lender's Appraiser can talk to you all they want, what they can't do is discuss their opinions, but they discuss facts.