Lenders won't value it off the income approach unless it is a 5+ unit and even then, the LTR market rents are more often used to determine value.

From my experience the median household incomes really determine the neighborhood class.

After reviewing your application, we’ve determined that, unfortunately, we are unable to move forward with your application at this time, as it does not meet our established criteria for income and (other established criteria) We appreciate the time you took to apply and wish you the best of luck in your continued search for a home. 

To determine price range, the first step is always figuring our how much you are pre-approved for; and that can vary significantly when you are looking at multi-unit properties because of the additional variable of rental income that can be included in qualifying.

Without having much info, I would need to know the financial situation of the 'close family' to determine a best approach.

The Board intends to reassess this decision to determine whether to recommence the redemption program or to continue to pause the redemption program no later than July 1, 2024."  

The biggest determining factors for STRs in the area are purchase or build price (and associated mortgage) vs rental expectations, that will help you determine net cash flow.

Yes, when there are multiple adult occupants, you would typically combine their gross incomes to determine if they meet the income criteria.

The answer to help you determine this is here https://www.biggerpockets.com/forums/51/topics/1164415-ne-re... ...

Available terms, interest rates, overall goals should determine how much you want to finance on properties.