I just got 6 boxes of books yesterday that have been stored in a garage for 5 years (and there are still 15 more boxes to get). There is no water or other liquid damage and none of the books smell like must or mold. However quite a few of the paperbacks are warped from the high humidity here. The warping is not significant - I've seen worse just from books being jammed into my mailbox. I've compared them to the club wish list and only about 20 of the books are wish listed (they are older books, mostly non-fiction). There is one box of antiques I'll be posting on Ebay (being hardcovers, they are in better condition than the newer paperbacks).

So - for the books affected by the humidity - are they postable? If they aren't, I may not even bother taking the other 15 boxes, because I'm sure they'll all be the same.

Can you set them under other heavy books for a few days and see if they flatten out?

Do you have central air or a dehumidifier? I usually try to bring those kind of books into my house and let them sit for a while with the AC sucking the humidity out. That usually will help. After a few days of being dehumidified (is that a word?) I will put them under something heavy to straighten out the pages. Hope you can salvage them.

Well you could post the iffy ones on another site that allows descriptions. The problem with humidy is that it can cause mold.  I think you're just going to have use your best judgement on each book.

You could offer them as freebies with an order from your shelf. I would just go through them carefully and post on here the ones that don't look wavy and moisture damaged. 

I agree with all said here - but don't dismiss books that aren't WL'd.  Especially odd, old, and non-fiction.  Those are the kinds of books that people look for since they don't always know that they want it until they see it.  I've had the strangest books go so fast!  If you can straighten them out at least give them a try before chucking them.

Ruth

Well out of about 200 books I posted about 50 and so far 7 have been ordered. Most of the ones with the worst warping were those HUGE computer books from QUE and SAMS and since they are minimum 5 years out of date I'm just going to get rid of them. Out of all the boxes about 3 boxes were antiques so I'm going to give them a shot on Ebay - we are talking SERIOUS antiques here, stuff from the late 1800s, not stuff from the 1930s and 40s. About one box worth, maybe a little more than that, I am going to keep for now - there is a nice set of art books, 5 of those Most Beautiful Villages...books, and an almost complete set of Louisa May Alcott novels from the 1890s that are all going on my keeper shelves.