I am reaseaching into retrofitting an office buildings restrooms to save water and money. I want to find out if I can install .13 gpf auto flush valves on exsisting 1.0 gpf urinals and still have the urinals work properly? I just started researching this and have not tried anything yet as budget is a factor and there is no room for experiment.

Why not to install waterless urinals. Selection is great and water usage is zero. Milo

I agree with Milo.
A bit pricey at over $200.00 waterless urinals (see image) is just what you're seeking. Check them out at, Sloan WES-5000 Waterless Urinal, Vitreous China Wall Mount Fixture. Good luck b Tom