Qualifying for a mortgage primarily based on investment income can be challenging, as lenders typically focus on traditional income sources. However, some lenders offer "net worth mortgages," allowing borrowers to qualify based on liquid assets like stocks, bonds, and cash. Requirements vary by lender, with some, like Scotiabank, requiring a minimum of $250,000 in liquid assets. Working with a mortgage advisor can help navigate options, including alternative lenders, to find suitable financing based on an investment portfolio.