Welcome aboard. I hope you did get a deal, if it runs well you should come out all right. Not sure what you mean by "mint", since there are a few things missing:
>Front and rear fenders
>Tank badges
>Chain guard
>Sidecovers
>Centerstand
>Rear footpegs
>Stock seat
>Stock handlebar switches
>Speedo/tach/instrument panel
>Stock headlight brackets
>Front and rear turn signals
>Stock airbox
>The carbs are not original for a 78'. You might check the engine numbers and verify that the engine is a 78' motor.
It looks fairly clean, and none of the items listed would necessarily be a problem. I am surprised at the lack of turn signals, and the pod filters can be difficult to tune, but again, if it runs well you should be all right.