Using future rental income to finance Duplex

[Derrick Dill]

I'm a first-time home buyer from Southern California interested in buying a duplex. I'm a registered nurse a year fresh out of college and I want to buy a duplex with intent living in one and renting out the other.

I was pre-approved by a lender for 275,000$. In my area, the lowest for a duplex (in a reasonable area) is 350,000$. I was looking to find a lender who can use my future rental income or 75% of rental income to give me that extra little boost to make my dreams reality. 

Can anyone point me in the right direction or give me some tips?

Thanks ahead of time,

-Derrick