Do you turn off?

Just wondering, when you change lens, change memory card or battery?

Second, filename, why shouldnt I change filename from defa DSC0001.NEF to something personal. Like BOR0001.NEF

Third, you might know the 70-300 the old ancient one of the 90ies, the first version with autofocus. I can get it used at a price USD 50. Worth it? Its very nice and very clean.

The photo is my first Nikon Autofocus photo -- ever! As you might see, I let my d7200 choose too wide aperture, thus the AF system focused on my dog.
Its my brand new Tokina 12-28 at f/4, 12 mm. I might have something to learn yet ;-)

Yes, always turn the camera, grip, flash, off prior to connecting or disconnecting anything. Cards included.

Yes for me too.....

Always turn it off.

I rename files in post.

Yes, always turn the camera off.
And I rename my files in post.

Off and I use the name change capability in the D7100 by using something like _D7C0001 to distinguish the photos take with it (7 for 7100) from the ones taken with the D5300. Any other name change is done in Post.

Always turn off before changing/swapping things out.

Name changes if ever are done post