The bicentennials really aren't worth saving. There are tens of thousands, maybe even hundreds of thousands, in circulation. Chris
You need a cooperative bank for that. Translated: a bank wherein you have a lot of money. If you don't have one of those, after time, the bank managers catch on you're playing games, and they cut you off.
I have no way to tell for double die. As for returning coins, I just go to coin star and get cash back
When I was searching rolls, I opened an account and just deposited them. They never had a problem with me. I used the same account to pay paypal purchases. That kept ebay and paypal away from my main account at a different bank. Worked really well for me.
Picked up a full box of halves last month. No silver, but some nice hole fillers. My bank has free counting service, so back they went.
My bank don't have a coin counter. Did find 2 rolls today at another bank. No silver today. Do have 5 1974 d. I don't have any way to tell if any a double die.