After watching some interesting bits in a local camera store - sales guy with an xacto knife near the exposed sensor - taking my sensor loop is a good start. Also taking a few shots of a blue sky at f22 to see if anything else is impacting things. Burst mode shots, AI Servo shots.
Any publicly available 'stolen gear' list I can check? A box is a sure sign of a proper sale - but last thing I want to do is pick up a stolen one.
You can usually tell a stolen camera, they do not give you a address and do not have the original box, manuals, receipts etc, just what they grabbed out of someone's car or residence.
I'd recommend buying a refurb with warranty, or a new one while the Canon discount is going. $1400 for refurbs using the Canon CLP when they have them.
I was robbed at gun point in my home a year ago jan, and they took everything. They tried to sell my gear to another photographer. That other photographer found my biz card in the bag along with a client contract contract so he called me up and I told him what had happened. He suspected it was stolen because the camera was dirty. If someone is selling a high end camera, they are going to clean it up really nice. If it looks dirty, that should be a red flag. Also, of course, if you see a biz card in something someone is trying to sell you, MAJOR red flag!!
FYI thanks to this honest, awesome photographer, who is now my friend, the a-holes who did this to me are rotting in jail. Hopefully for a long, long time.
And yes, I got (almost) all my stuff back.