Well, I would say that is it worth the investment to build a costume website. Who are your audience? What do you sell? How much are you going to profit from your site? Basically the ROI, what is it going to look like?
Now if you are selling mugs and t-shirts I would recommend Wordpress plugin, That would do the job. But if you are manufacturing the product, I would recommend costume website. It all depends on you cash flow, it might be better off spending $7000 on something else that the company can benefit from.
Hope that helps ...
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