I'll kick in. How many rental properties do you have?
To get regular residential mortgages? Its probably not happening.
To get an in-house bank/commercial loan? Sure. Once you have four plus properties, it starts looking like a business. Lower LTVs, quicker repayments.
This is my experience, both as a FIREy person right now who just quit my job and explored a mortgage and as a former business lender for fifteen years