If you plan to live in one side of a two-family and rent the other, minimum down payment follows the standard owner-occupied rule, 5 percent up to $500,000 and 10 percent above that, since it is treated as your residence. A condo purchased the same way follows the identical rule.
The two-family's income only counts for financing once the second unit is a legal, permitted suite, which a lender and an appraiser both check independently. A condo's ongoing fee is fixed and predictable but buys you out of most maintenance decisions, including ones you might have made differently yourself.
The right answer depends on whether you want income with responsibility or a fixed cost with less control. Get your hand-reviewed valuation from Joel Dyck.