Skip,
You are faced with the very same problem I was years ago. You do not know where to start. Your best option on the boards is exactly as your stated, divide them up by era/manufacturers. Being untested or partially working makes it difficult to put a price on them. I often buy bulk lots of boards/displays to refurbish and can tell you a list of what is included in a lot is a must. Everything I buy I assume is not working despite how it’s labeled or presented. Start small and work from there. Good luck.