It was a win win for both because the seller wanted to reduce his tax liability and sell all three locations together and we wanted specific terms with the seller financing.

I have a low credit score (slightly above 600) due to carrying high credit card debt as well as having some charged off CC's from my college days, however the statute for those to show up on my credit report expire in August of this year so it should provide a sizable boost to my credit score, in addition to my plan I have in place to reduce my total credit usage from $12,000 (out of 13,000 available) down to about $4,000 by July (hopefully lower!).  

If you think renovated units will get $400-$500 more, maybe you offer existing tenants to stay in non-renovated units for a $250 rent increase) and create a "win win" for you not matter their decision.

There are not often deals out there, and sometimes you have to buy at market price - and that still can be a winning strategy if you buy the right property. 

If the other units can pay for some or all of your living expense then I would consider it a big win - especially at your age!

All in all, it's a win win, as I pay less rent, help them with the mortgage, and at the end of the day, we'll turn around and rent this house out, I'll just need to come up with the half I owe.

Do you use your own cash or credit card?

I've never used a credit card in my life and I've never taken out a loan. 

Sounds like a win!