My chances of getting approved for a mortgage

[David Jesse]

Hello

I'm considering buying my first house after years of savings. I want to buy one that has a detached guest house. I would live in the guest house and I would rent out the main house.

Right now I'm considering north of Los Angeles area. 

Would renting out the main house help with getting approved for the mortgage or does that hurt my application? Based on my calculations my mortgage would be around $3500 and the going rent is about $4500 a month.

I would be putting about 30% down.