A few years ago I bought a 79 GL from a pic on facebook for $400. The ad had 30 or so offers of pay on Friday, can you deliver, can you fix it, trade for a snowmobile, etc. I told him I'd bring cash, a helper, a trailer and come when was good for him. It needed all the usual things, I spent another thousand on it and rode it to Sturgis that year.
Last year I was offered a nicer one for a cool hundred, (gift) so I sold the 79 for a thousand and ordered all of the parts needed to refresh the blue 78. I left the vetter bags and fairing on and rode it to Sturgis again. It's called the 20 year sleeper or old blue. They do sell better naked, my wife likes riding it better than the cb's so it's my two up and long ride bike.
I like them and don't get why they are so cheap except, most guys can't or won't learn to work on them themselves and it's too expensive to hire it out.