Take off sparkplugs and see if it turns with crank.. it does have kickstart? You might want to put some oil or even aft on top of Pistons.. check valve clearance with feeler gauge. Check oil if there is water on top. Check spark. Open carbs and clean them through.. fuel that we use nowadays and get really bad. Cam chain tensioner should be looked at, so it's not bottomed out.. wheels brakes, brake oil, suspension.. get ready to change battery.
But in the end of the day, it's Honda, it's fine.
I got 77 cb500k3 and 78cx500.. they are great fun.