Automatic Quote System

I have several products for my site that I make custom. I run my site on Joomla 1.0.12 and I want to integrate an automatic quote system that will give my customers all the variables to choose from and then they can pay through paypal or another source like authorize.net. The only issue is figuring out shipping. I need someone that can make this process easier for me and that can easily integrate into Joomla. I want to be able to change the prices as time goes so I need this to be manageable also. The product has about 20-40 variables depending on what we can put together.