I have been doing alot of thinking about Repts because I have them for my travel cages. I ran into the same problem as far as how to hook things in them.
One solution I came up with (that I haven't seen mentioned on the board) is the black plastic hardware cloth. (like alot of
toys are being made out of) Cut the hardware cloth to the size you want and zip tie it to the plastic frame of the rept. It provides lots of surface area to hang things and is easy to wash as well. (I have whole cages made of it) You can even go horizontally with it to create a shelf at the middle supports.
If you don't want to use zip ties to mount them (if you want to more easily remove them) just put the zip ties around the pipe but not tight, then use lanyard hooks to hook them to the zip ties.
Hope this helps.