It's a fair bit of work and money to start with that for a project. It all depends upon how much the Seller wants, how much time and money you want to put into it, and whether at the end of it, you'll be over the moon to keep it.
You will invest far more money into the project than you will recover selling the bike. The '78 is also fairly "undesirable" as a high retail bike, but good bikes. They simply don't command the money the earlier K bikes do.
And of course, a title for the bike is another consideration...
Welcome from Richmond. If its a project bike you seek, there are other better deals around. If you want an inexpensive, project thats a runner, those are around too. We can help you find a good value, good bike that's less involved (if thats your goal).