I don't have a US credit card or any other means of alternative car insurance, so I need CDW when I rent in North America - this means, in general, using European OTAs or directly via avis.uk etc.
The code I have found useful for this is H811101, about 15% off for US/Canada. It's a general North American Avis offer(from Europe).
After sifting through the various European sites, it seems that avis.fr and
www.avisautonoleggio.it have thus far offered the best rates.
I'd be glad to learn of any other codes/sites...
D.