Looking at improving the data, access to the data to improve deal and deal analysis. 

Sounds like you need to improve your credit score and/or establish a credit history and save up some cash.

I would practice by evaluating a few dozen properties to get you comfortable with this process and then you can move on to later steps.

There are lots of things that you could do to improve the cash flow of this investment as well, which it sounds like you are already thinking about, assuming your initial numbers are correct.

It takes a lot of practice, a lot of not responding right off the cuff when you have to deal with junk, but it does pay well if you can gain the respect of your tenants, and take care of their repairs whenever they call. 

I'm make better offers if I see the potential to improve the property and raise the rents.

It was my thought process, that as the area continues to improve, my property value will do well also, while I make money.  

Glad to hear people are digging in on the neighborhood, my portion (Glendale Blvd and Alvarado) certainly has room to improve...  

Going in with practically no down payment, what is the best way for me to gauge how profitable my investment will be?

If he has been doing this for 10 years and you have allowed it with no formal, written reprimand and request to not make material changes and improvements then you are not going to be able to use that argument in court and if you do you should be ashamed.