I think it is a good deal for a bike that works at $10 but some things interest me. Judging from the over the BB cable routing and below the TT cable routing it looks more like early '80s. the lack of a derailleur hanger makes it a lowerend machine but it has columbus decals seems odd to me.
Are the seat stay capes rounded or they concave or 'spoon' shaped, they look rounded in the pics. can you take a pic of the fork crown? what are the fork ends? does the headtube/downtube lug have a B stamped on it? is there anything stamped on the frok crown?
The crank is mostlikely an Ofmega like Bianchi used alot in the mid '80s.
OH what is the front brake and the headset? and the size of the seatpost?