How much rental income needed to qualify for mortgage loan?

[Aubrey Cook]

How much rental income from investment properties is needed for someone to qualify for a mortgage loan if the person has no other source of income? Like say you want to buy a $1 million property with 20% down for example...how much do you need to be getting each month from rental investments to qualify? And do banks look more at net rental income you get each month (minus all expenses), or do they only care about the checks you get in the mail each month?

Also as a separate but related question, can you get a cash out refinance if you own a property free and clear, but only have income from rental investments? Is this harder to do than getting a regular mortgage loan? And does it make a difference in difficulty if the property is a commercial multifamily (5+ units) versus a residential?