The amount of work needed may depend on how long it's been sitting. These all need a little something done to them, lol, even the ones that look good to begin with. The front brake system may need a disassembly and thorough cleaning, carbs may need a cleaning as well. There are many little "fixes", upgrades, and improvements that have been developed for these. Most are well documented here on the forum. Even a long time owner probably wouldn't be aware of some of them if he wasn't active on forums like this.
I would be quite happy with a nice condition '76 model. The 34mm forks are probably just fine for normal riding around. The early type front brake caliper is actually supposed to work very well because it has 2 moving pistons. The later version only moved one piston and worked fine, so an early 2 piston unit could work even better. '76 was also the 1st year for a linked carb set-up or carb "bank". These are much easier to sync, and stay that way longer, than the earlier separate carbs.