I like looking at what dealers want to buy especially for modern since much is sold at a discount of face. This is the general buy list for Markest Stamps who advertises in Linn's regularly.
Forever sheets being purchased at 80% face.
He has a buy list for specific sheets and found one on his buy list that he offered for sale. For Scott 4521 (64¢ Wedding cake, $12.80 face), he will pay $40 and sell for $69.95.
My 2021 Scott prices it at $50. Anyone have a later Scott?
The wedding stamps in general seem to command some premium over the usual discount.