There are many camera owners who like to have the latest version of their favorite camera.
They often sell the old camera so that they can afford the new one.

If you can get a used camera from such a person, you could get a bargain.

Each time a new model comes out, they add more bells, whistles, and megapixels; but the overall image quality is seldom improved.
If the older model has the features you want, it will make a good first DSLR for you.

I still use a Canon 20D and find that it works for me.
They have not added enough bells and whistles to make me want to upgrade yet.

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As long as you pick a used camera that is in excellent shape, I see no reason not to buy a used camera.

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