Just go in and ask.
Prudential CA Realty
Be sure the builder doesnt add this incentive to your purchase price.. Things to ask about...
What you'll probably find is that some upgrades are priced competitively while others are way out of line. That has been my experience and one of the things I've helped clients negotiate wisely. Sometimes a $5000 credit to closing costs is worth $10,000 of upgrades at their prices. If there is any room for them to negotiate you'll want to do it before you sign the contract.
On a side note, I've frequently found discrepancies between what a builder has on site for upgrades and the actual materials at the design showroom. Not better or worse, just different. For this reason alone I'd go check out the design center first.