I'll hopefully be purchasing a 70-200 2.8 Canon tonight for 800 bucks off craigslist.

Is there anything else I should look for besides dust, mold, scratches, rattling noises, sharpness and focus?

Ask them why they are selling it.

If it feels like a genuine answer and that they seem to be missing it then you can probably trust them. [Upgrading to a better lens, didn't ever use it.] Are two good answers from someone I would trust.

Obviously make sure you take some pictures with it and if you notice ANYTHING weird don't buy it.

If the persons camera looks messy or their car or house etc, be more careful because generally if someone doesn't care for that stuff the lens will be in bad condition too.

Good luck!

yo can chec how meny pixel a camra has if it don't not includ pixel it will work better. hope thet help!

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