Re: Ugh, Clarinets!
I'm a flute player and can blow sax and clarinet. I also have a degree in instrument repair. The first order of repair and other life threatening changes is "do no harm" . Unless you are confident and competent at repair I wouldn't go about modifying tone holes. I do specialty repairs like making tenons, sockets and tone holes as well as keys and other stuff. Your repairman is likely charging you more for the PITA factor for having to fix repairs that you should not have attempted. Don't get me wrong, I'm all for DIY, just be aware of the cost if you can't DIY and have to send it to your repair person. FYI, IMHO clarinets are really pretty easy to repair.