[MikeDubreuil]

I don't think the rules are unclear at all. I have said this before and I will stress it again, only those looking for loop holes will find the rules unclear and inconsistent.

Here are the rules in a nutshell:
Every part on your shipped robot must be obtained during the build time.
It really is that simple folks.

I built a prototype pre-season. Do I really need to buy all new parts?
100% YES

AndyMark-
If AndyMark wants to sell you a tranny, you need to buy it after kick off. Or you can't include it on your robot. (Yes, you can buy one pre-season to play with, however, the one on your robot needs to be a new one.)
How do they bill it?
When they bill the transmission there is a real judgment call that needs to be made, "is an AndyMark transmission an off the shelf item?"
I feel the answer is no. That means teams must account for both parts and labor. AndyMark can bill the item however they would like. My recommendation is to bill for both parts and labor.

Pre-built-
Pre-built means: a team buying a mechanism from someone during build season. During build season means you did not have the parts producing that mechanism in your teams possession prior to kick off. Therefore, NO 100% can you just slightly modify last year's robot to this years game. You can use new parts to recreate the mechanism, but those parts have to be NEW TO YOU.