Hi VegasFD,
If you are looking for a professional marketplace script that will do not only Product (like pro bids) but also give you the chance to setup a reverse auction marketplace like Guru, Scriptlance, GetaFreelancer, etc then you might want to check out ILance, a product I've been working on since 2002.
There have been a few sales from NamePros members for the ILance solution, as you can see from the thread below (view the most recent posts, you'll see people are very happy with that is available in ILance).
Here's the link with more details:
http://www.namepros.com/scripts-for-sale/409249-start-powerful-marketplace-2008-earn-like.html.
I'm more than positive it has everything and more you'll need to do (in terms of setting up product auctions) but also gives you the chance (when you want) to roll out with Service Auctions (freelancing style) as well as the popular Lowest Unique Bid auction type (like SilverTag.com) I'm sure ILance has what you need and then some
ILance is priced to sell. We support the product and provide a community to get questions answered very fast and professionally. It is priced a tad higher than other solutions but the more you see what it can do the more you'll enjoy the investment made. It's not really about you -- it's about your end users. End users find ILance to be very easy to use, to the point and gives site owners the chance to stand up professionally very quickly in the marketplace.
PS - The ILance Administration Control panel is the best in the business. It offers you countless areas of letting you tweak everything, turn product on, turn service off, vice versa, or use both Product and Service together. That's up to you.
Let me know if you have any questions! Good luck with your decision!
Regards,
Peter