Potential Opportunity - 1st Time Investor

[Julie Vilinsky]

Hey Everyone! It's my first time posting or being involved in anything real estate. I've always wanted to own property, but for the longest time figured it would never happen. Found the Bigger Pockets podcast and have been listening for 2 weeks and love it! Decided I can do this. So I came across this potential opportunity and I don't want to miss it, but don't know where to start. Here's the facts: 

Single family 2 bedroom 1.5 bath house in small town between Visalia and Fresno, CA (Dinuba). Husband has known this family forever, good friends with their son since grade school.

He's working on their place to fix it up so they can sell it. I believe they own it outright. They just moved into a condo and it's seeming like it's just a headache for them and they just want to get rid of it. We'd like to buy it from them, but we don't qualify for traditional financing (too much debt) so seller financing is the way we want to go.  How do we make this attractive to them? We are willing to do the work and even get rid of all their junk in there for them. I think we can add a third bedroom easily to up the value right away. It looks like a good opportunity to fix and flip, but I'm almost clueless. What numbers should I be looking at (other than the obvious)? Having never done any property buying ever, I don't want to miss any key details. What do I need to find out about the property? Anyone have a handy reference you can point me to? Thanks in advance!