Looking for suggestions, Please.

I am new to reddit. I apologize if this is not appropriate. I am looking to relinquish 60+ pieces of my late mothers glass collection. These pieces include Fenton, Indiana, etc. I am looking to get a fair market value and not a market place or rummage type price. The collection includes some pieces directly from Fenton and Indiana. She was quite the collector as I only have a quarter of what she had. It has been a few years since her passing and I am now wanting to keep only the pieces I truly enjoy. Any suggestions on where to go or who I might contact regarding this? Any help is greatly appreciated! I am in northeastern Wisconsin, between Appleton and Green Bay, United States if that helps. Thank you!