How much down for apartment buildings?

typically how much do you guys put down for your multi-family/apartment complex acquisitions? 20%? (assume the building is at exact fair market value, based on its current income)

Well, frankly, the less you can put down the more money you have to invest into the property or into other properties. But, that being said, most of the time the down payment amount is dictated by your lender. Typically lenders require 25 - 30% down on a multi-family property though at time they may accept 20% down on 2 - 4 family properties. You should check with your lender and see what they require.

Ditto.
Depends on the lender or the originator of the loan. Some may typically ask for 20% while others ask for 30%. Some may even agree for a 50% down upon mutual agreement. This case is of course more ideal for the buyer if they prefer shorter payment terms and lower monthly payments. Gather the specifics and hope you’d get the best deal for you!