Out of college, ready to invest

[N/A N/A]

Hello all!

I am making 120k/yr and living in a small city in Texas.
Houses here cost 40-100k. I would like to buy a house and rent it for a little higher than the mortgage.
If I can manage to do this can I keep getting mortgages for more houses?
For example, say I have a house with a mortgage of 500/mo and I rent it out for 750/mo, would I be able to go to the bank, get a mortgage for a second house after showing them the profit from house 1?

I ask this because I learned you can only get mortgages for 3x your yearly salary. But does a rental property count if you are beating your mortgage?