10 percent downpayment on investments

I have purchased 2 properties thus far which have been single family row homes. Both of which I put down 20 percent which is the standard but minimum was 15 percent.  

For properties with 2+ units the banks want 25 percent minimum unless you are occupying the property.  My lender says there’s no way around this regulation.  

Does anyone know of ways to purchases 2+ unit properties with a 10 percent or less down payment?  This is with NOT being an owner occupant.