OK imm currently developing 2 sites localy for my ecommerce project. 1 using E-commerce module and the other using Ubercart. I would love to stick with Ubercart but theres 2 things that i need.

Are there modules that will enable me to add a discount for preferred clients and distributors and to add discount for large quantities?

Is there any module that will store customers addresses so that they do not have to re-enter them every time?

I cant find them if they already exist.

*** OK found the Discounts module here?
http://www.ubercart.org/contrib/143
Make sure you download the latest version... for me its the one that reads:
On January 7th, 2008 detour says: