Sorry, GreenFlag, can't go with that.
I'd say that with under $ 100, often under $ 50 in a logo or template change any of those Fantastico carts can look as "professional" as those costing thousnds.
In fact, as far as shopping cart design goes, the OSCommerce look is almost universal for most online retailers. And most of the large retailers all have basically that same look, as well. Header up top, menu down one or both sides and a footer with some links. I think it's what the buying public expects and anything far from that probably loses sales.
Crisp header, several popular items above the fold on the home page and then items in categories. That's pretty professional.
The trick is not in the site design, using any of the freebies with just a few touches will keep people on your site, it's getting them thete that takes the knowledge and skill to bring about. I don't think anyone will click away from those sites because they don't look professional.
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