Just a thought Jim, but it appears that you live in Pennsylvania, so you are probably within a 3 hour drive of York.
I would rent a table at the next York show, pack up all of the stuff, and man a table for three days to sell it. (Don't take any "smalls". I.e., low price items that take up table space. Set a limit of something like $30 and above.)
Mark it 10% to 15% less than fair value, and give additional discounts if people buy multiple items in lots. Put sets of related cars together in advance for bulk sales.
Advertise in advance by posting a list here, and make it cash sales only. (Unless there is a trusted dealer from whom you will take a company check.) Post and sign it as a Private Collection Liquidation Sale.
Hopefully, you can sell more than half of the stuff, and while you are there, go to the other tables and tell them that you are going to auction off all of the remaining items 2 hours before the show closes. I am not sure if you can run an auction from your table, but there should be some place very close by where this can be done. Open each bid at 50% of fair value. You would be surprised at how often a frenzy of bidding can occur.
Anything that is priced at a real bargain may very well be bought up by other dealers before the show even opens.
Be sure to bring a counterfeit detector pen and check every bill $20 and above. And be sure to bring along at least one helper.
It would be interesting to know approximately how many items you have. 100? 200? 500?
Even if you are planning to have a dealer come to your house to look at the entire collection, you are going to have to prepare a complete itemized list of everything and the prices in advance, plus pack it up yourself, unless you want to pay $40 to $60 per man hour for "packing charges." So, since you are going to do that stuff anyway, take it to York.
I have doubts as to whether a dealer or auction company you contact would want to take "everything" in your collection. They will almost certainly pick and choose. If you make them take "all or nothing", then they are going to pay you very little for the items that they don't want.
So go to York first. What have you got to lose? Yes, it will be exhausting, but getting rid of a large bulk of items in one swoop will be worth it.
Mannyrock