Cleaning and Stain Removal - Advise on cleaning walk-in showers

I recently quit the corporate world and took on cleaning houses as my occupation. I am one of those people who actually enjoys cleaning, so it is working well for me. One problem I am encountering is in homes with large walk-in showers. These are tile flooring and walls, with glass exterior doors. I've got the cleaning part down but can NEVER get one cleaned without getting wet. Is there an attachment of some sort that can be placed on the shower head to keep me from having to continuously fill up cups of water for the rinsing down after cleaning. Any help appreciated.

Jeff Campbell has such a gadget at http://www.thecleanteam.com/catalog_f.cfm

You can also fill up a bucket of water and dip water with the cup to rinse shower walls and then use a squeegie to wipe them down.