Let’s talk Percentages %

I’m it a seller … I’m a collector, but I need to sell some of my duplicates in my closet (probably around 15-20k worth)… as per the wife.

After chatting with allot of people in town (central Texas) sounds like a current average people are buying is about 80%. I’ve seen some people posting that they are willing to pay closer to 90% for older stuff but haven’t really seen many people that will do that.

My questions are …

Is 80% a current “standard” as of now?
What is the average in your town?
What have you seen?

Thoughts!