How to clean and play analog reel to reel tapes

I have come across several analog reel to reel tape which are falling apart. The oxide/binder appears to be falling deteriorating making the tapes very difficult to play. The heads on my reel to reel player tend to "gunk" up after only a few minutes of play time and require cleaning before the tape can play again. Even then I can hear a "squealing" sound from the tape that is playing. These are recordings of my family (e.g. voice of my great grandmother etc) and cannot be replaced. Some are over 40 years old. I would like to transfer them to CDs. Can someone help and guide me on how to best handle this task. Of course, the first step would be to clean and play them. Any suggestions on the least expensive route to do this. Your help will be greatly appreciated.