Buying Duplex with no renters

[Michael Malloy]

We're wanting to put in an offer on a duplex that currently has no renters on either side. We plan on house hacking this by living on one side and renting out the other. However, neither side currently has a renter in it. I need the rental income to offset the DTI for the loan. So my question is...since we can't rent it before we officially own it, does this mean that we're SOL unless the seller for some reason decided to spontaneously rent the other unit before closing?