Pre-sale question about varients &characteristics

I'm in the process of trying to revamp our site with the new Joomla 2.5.
Currently I use Virtuemart with an old hack that is getting dated.
I think your cart might work but haven't been able to figure out an easy way to do what I need. I'm up for suggestions about organization of products etc...

I sell metal handrails.

1. There are lots of variables include railing style (3 types), size (6 or 7 per style), (post types twisted, baseplate, in ground) & hardware (2 to 4 types) Is there an easy way to start with a base price and have the variables add to it? For example +$45 for special posts, +$8 for hardware. Or must you create variants resulting in a multiplying effect where you actually have hundreds of products and lots of price managing.

2. On taking orders I also have to collect two basic pieces of information regarding customer's measurements. Does the essential or business handle this? You can see our current site at www.zottolafab.com

Thanks for your time

Okay thanks, That's why in the free version I can't see how these work but I can get an idea in the demo. It's a lot to think about.