I got my C&R license a few years ago and have never used it.
I probably am getting really close to having to renew it.
I took it to a number of gun shows early on but never found anything I had to have for the right price.
The few times I tried buying something online the seller didn't understand he could ship directly to me and I lost out.
My FFL charges about $80 to transfer private sales. He is $5 cheaper than anyone else within driving distance. I ain't having good luck with my C&R so far.
But, I'll renew it, and try again.
The only part that keeps me up at night is if I use the C&R and log each purchase and sale in my collection, I now have a record that will eventually be in the hands of the BATF (when I die or turn in my license and records).
Doesn't keep me up for long... just sayin'.