Companies I have worked for typically do multiple bid RFQs with vendors similar to what Mike is stating above. It helps if you have vendors you know and trust, or have friends who recommend them and build a relationship. Having a local representative can also help. The tooling costs can vary greatly and of course if you can guarantee a high quantity they can disappear.I would think it would also help to have some ballpark notions in mind to aid in negotiating. A great OEM/ODM will help by giving you feedback as well to make the production more cost effective.