Rental qualification is a lender-policy comparison
Lenders can use different rental worksheets, vacancy assumptions, expense allowances, lease evidence, and add-back or offset methods. The same property and borrower can therefore produce different qualifying results before the rate is considered.
Model the subject property's real rent, taxes, heat, strata fees, financing, and operating costs. For an existing portfolio, include every mortgage and the documents needed to support each lease and expense.