$50 in my opinion would be rejected. $100 might get it, as the ad is practically begging for offers.

It looks like it is very clean, decals good, etc. Look at the pic with truing stand and bike tools in the background. While not a guarantee, it means it is probably up to date on lube, tires look new, etc.
Crank looks like a repurposed mtb unit and newish looking. Nice saddle, bullhorns, brake, bar wrap all look nice.

If it fits, I think it is a good deal.