Considering buying a quad as my first real estate adventure?

[Jason Halka]

Considering pulling the trigger with a quad plex. All units are filled generating $1725 a month in rents. Roughly $105 in tax and $300 in operating expenses. I have a HELOC ready for $23k. I would put down 20%. The seller wants $79900 for it. I viewed the place myself and had concerns about a roof leak, foundation issues, and a damp basement area where HVAC is located. A friend (who did real estate for a while) suggested to offer 70k with the stipulation of everything passing inspection. The quad plex is right next to the police station and within walking distance to two universities. None of the tenants are college students. It would be my first time doing any real estate besides owning my own home for 15 years. Any thoughts would be greatly appreciated. Thanks