Don't forget that you'll also need to be able to edit those pictures and videos. And you need to be able to put it all together in a web page
While we have no age restrictions that I know of, I doubt that they would use anyone under the age of 18 due to contractual obligations.
But then, who knows.
What I would suggest is: Buy a product that has not been reviewed by RCU magazine. Assemble it taking pictures along the way. Shoot and edit a video wrap it all up in HTML code and submit it. Who knows, maybe you're a natural
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http://www.rcuniverse.com/magazine/rules.cfm