If a tenant is screaming at me about something, I just shut up, let them say what they want to say, and then address their issue in a  professional manner.

I was doing a screaming sub too pre foreclosure . 

We've sourced hundreds of deals from those 2 sources alone, in addition to approximately 9 other strategies we have honed over the years to fill our funnel with screaming good deals (where nobody else knows where to look....Happy Hunting!

I think if your going to go big and make a business out of this it can be fruitful.. other wise if you have limited capital its like the OP said you make less than flipping burgers.Plus your capital is not liquid and if your cash is sitting there and that screaming deal comes up what then?

The current market is not just a little inflated, it is absolutely crazy (at least in the areas I know and hear about).If I were planning on buying Real Estate, I would wait.....unless of course there is an obviously screaming deal....

If you buy that screaming deal with cash and find later you hate not having a mortgage, get one. 

The fact your rents are so low screams D class neighborhood which scares me.

Guess that is why everyone is screaming about the need for rent control.San Mateo 3/2 selling for $1.6M (roughly $8400/mo PITI) would rent for roughly $4200/mo.But that is still roughly $4K/mo you could put into investments elsewhere.This should solve your DTI issue, but may, or may not, be a better investment in the end than just sticking with your primary.

Then there were three way calls with us, our contractor, and his subcontractor screaming at him on the phone for not being paid for our project and prior projects they had been engaged in. 

but you have to be living under a rock to not understand why insurance companies don't allow them.I had a German Shepard one of my favorite that I have owned over the years.. she bit someone on the butt who walked into our house un announced and then turn ran and screamed..