I spend a great deal of time at the bookstore writing correspondence exactly like this one I sent today. I hope this info is helpful. I truly feel all of us booklovers are in it together, but as a bookseller, I am obliged to contend with dreary marketplace realities.
Thank you kindly for thinking of us. I am not interested in acquiring this collection. I do all I can to discourage people from making lists. The effort you put into that is a tiny fraction of the effort it takes to turn those books back into money one by one, slowly sold at prices probably half of the values you assigned them, which are, with all due respect and I am truly sorry to say, meaningless to me. I looked it over fairly quickly and casually, because I knew from your description that there would be only a smattering I’d want to take on– James Joyce, for instance.
My 28 years in this bookstore abounds with examples, but here is an illustrative one from yesterday, that indicates the difference between being a book lover, or book heir, and a bookseller obliged to survive in the real marketplace today. A lovely gentleman, longtime customer, brought in a stack of vintage Little Golden Books. He had researched, listed, attached high prices. However, nearly all of the books had torn or cut pages and scribbles. That makes them worthless as collectibles. In his case, he was pleased to exchange them for a few of our books, and I will sell the Little Golden Books at low prices because everyone finds them charming, and donate some to Little Free Libraries.
Good luck to you and your books. You might be able to find an online-only dealer without overhead who is willing to spend his time on them.
sincerely,
Kim at Duttenhofer’s
Duttenhofer's Books 
Well stated- hope it helps.