Where do I get the numbers to analyze whether I have a good deal?

[Taron R Colenburg Jr]

I am new to RE investing. I work for a private company that paints houses and apartments, inside and out. What I have noticed since I started studying real estate, is that most of the houses we paint are houses that are being fixed up so that they can be put on the market. I am a very social person and I always talk to the home owners. I feel as though I have an advantage because I know the houses are going on the market before anyone else, so it's kind of like I have first dibs. I just don't fully understand how to analyze a deal. I try to utilize the BP calculators, but I don't know where all the numbers that I'm supposed to plug in come from, therefore I don't know whether these houses that are going to go on the market are a good deal or not. Any help?