Value of a 68 Beetle in poor condition

So, I'm interested in this 68 beetle, and would like to know what it is actually worth. Mechanically, it is sound, the engine is in good tune, rebuilt 5000 miles ago by the previous owner- the clutch and Tranny are both fine too, however, the interior show severe wear, with stuck windows, broken window handles,  rusty heater vents, a couple of water spots etc. One of the seats was temporarily removed and needs to be reinstalled, it comes with the car. The Exterior shows some rust on the bumpers and such, and the side and roof have been tagged with graffiti. If the graffiti could be removed without harming the paint, the rest of the paint would be in good condition. The frame has some surface rust, but nothing that would indicate a structural problem.