GeekBoy wrote:

The PVC toilet waste flange is now way too low with the new
floor/tile. How can I raise it an inch without cutting the PVC and
gluing a new flange (it's not accessible, so I can't cut it)? Should
I buy one of those extenders from HD and push it on? Won't that make
the waste hole thinner than 3"? Are they reliable? They say they
don't need a wax ring -- do I believe that, or should I place one on
top of it anyway? Is there a neat tool which I could use the cut the
PVC from the inside, then slide on a new PVC and glue it?
Thanks!

There is indeed a neat tool to cut the pipe from inside.
You'll probably have to ask at a plumbing supply house.
There is also a flange with an extended "neck" available
so that you can slip it right over the now shortened pipe.

I don't like to see closet connectors less than 3" used,
although 2" has been done successfully and many new toilets have
narrowed outlets.

There are "flange extenders" (Oatey) which you can layer on top
of the existing flange as another possible solution.

Jim