[Eric in the Ozarks]

Look up the nearest gun shop (not a chain store) and call them. Explain what you have as best you can. Place the guns in the trunk of your car, wrapped in towels. Have the gun shop owner look them over, unload any that are loaded and give a value based on Fjestad’s Blue Book of Gun Values or a similar publication.
You might also pick up a copy of the book and look them up on your own.

[reg45]

If there are several firearms involved, a reputable dealer may actually be willing to come to the house to assist you in deactivating and properly transporting them to his store.