Indispensable items for me -- I had decompression/fusion surgery 10 weeks ago:
Shower chair
Handheld shower sprayer
Suction cup holder to put on shower wall for handheld sprayer (available for about $10 onliine)
Long handle bath brush specifically for private areas ($10)
Misc. suction cup hooks for placing shower items at your sitting level
Toilet aid for wiping ($10)
Toilet rails
Walker to help me get on and off the couch in the early post-op days (bought one for $4 from Goodwill).
Grabber -- I was shocked at how many things I could do with a grabber, such as laundry without assistance.

And don't forget to walk. I averaged 2500-3000 steps per day for the first two weeks and more after that. I'm now pretty much back to most of my routine pre-op activities. I attribute that, in part, to following doctor's orders on intermittent walking throughout the day.

Good luck!