How to buy second home, and turn my first home into a rental

[Rena Spooner]

Hi Everyone, 

I bought a 3 bedroom, 2bathroom home on the California coast at the bottom of the market in 2011 at a 3.99 interest rate. I also have a 4th backyard bedroom on the property. I would like to buy a second home and rent out the first. I'm in a very hot rental/airbnb market and could get great cash flow. I have rented out/airbnb'd rooms on the property in the past, so I'm familiar with demand. I'm a single mom, with an average-moderate income, and not much savings besides retirement. So, I would need to do a 3.5 percent down on the second/ new primary residence home. My son's child support check dries up when he graduates high school in June, so I was hoping the rental cash flow could partially replace the lost child support and help pay for his college. His biological father has said he won't help with college. What steps do I take to make this work? I want to purchase before the child support ends, as this is a significant part of our household income. I'm confident I could have a renter before even moving out due to demand. Positive cash flow potential is $1,000 per month, more for airbnb. I just couldn't get approved for two mortgages with my income. I would appreciate advice on what steps I should take.

Thank you!