The first thing you need to know before you talk to an auction company is know the fair value of what you have. Then you can determine if the fees from them make sense. You could be better off selling all of it to a private individual for a fair cash price. There are collectors that can and would buy it. Auction fees can eat you alive. Without knowing what games/condition I don’t know if you have anything of value or lot of junk. I have seen both. There are ways to screen private buyers to make sure they have cash for this type of a sale and can remove the items once purchased. Most important if you should go that route is to set an agreed upon reasonable time items must be removed and stick to that. DO NOT become storage for a buyer. Use a broker/lawyer for such a large transaction to draft a sale agreement to avoid any issues of the terms of sale and transfer of funds.

Hope that helps and good luck!