Phil,
You really get what you pay for. Especially with designers. Verify referances before you start with anyone. They can always say 5 bucks an hour and charge you for the hours they sleep because they dreamt about your project.
Make sure you put a limit up front on how much you want to spend on design work. that might help speed things up.
I can recommend some good ones I have worked with before if you like.
Prototypes are vital in my opinion. Not just because it's what I do. LOL
I work with companies like Boeing, Rockwell, and Black & Decker. They all get prototypes. They go through several revisions in fact, on every part. They have some very smart guys too, it doesn't matter how smart you are. Until you put it in action you cannot know how well it will work. Once you see it in action changes will have to be made.
The design will evolve several times once you get the prototype.
I cannot think of any instances in 15 years of prototyping that someone went to production with the first revision, not one.
Plus nothing connects a person to a product like tactile contact. Whether your selling the idea, looking for venture capital, or marketing it yourself.
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Chris Wentworth
Owner
Action Prototype & Urethane Casting
714-978-0333