Understand the history of the brand you're looking for. Professional brands carry a high standard and even used equipment won't come cheap if the pro's have been using it forever. So start with a price range in mind and think about your needs. If you plan on spending over $600 for a basic setup (camera, mic, sound mixer) then you probably can focus more on your wants. But if you are like the other 80% of the digital video world you have to start with your needs first. After you have assesed your needs based on the job you need to do, you're ready to do some shopping.
In this digital age we live in it seems almost common practice to first turn to sites like Craigslist, and Kijiji, but why not first go to a pro shop? I realize that you are not donald trump but pro shops do sell used equipment. Also, professionals earn their living from their equipment so they have most likely taken exceptional care of it. No matter what route you choose be sure to see the equipment in person and test it out first. Even if the owner is breathing down your neck, it's your money so take the time to try everything out.
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