Very true.
Having been through several "buys" with Circa, I have learned a lot about selling jewelry!
Circa may not be the right choice for OP (or anyone else!) , but the plus for using for Circa is that it takes little effort by the seller and if Circa's offer is accepted, you have your payment immediately. I brought my things to their office in NYC and walked out with a check. I took back home the things I didn't like the offer on.
They also can do all this by mail if the seller is not near a Circa office.