Tangential to another thread about disposing of old possessions, I'm clearing my dad's old books. I've sold one old book on eBay (signed) and a very nice fellow paid a good amount for it - old Scottish hill walking book. I have some others, some signed - he is interested but I have no idea about value, and being so niche there is nothing (even unsigned) on eBay to get a fair price.
Stick a high-ish guess and then work back?
Just stick them all on eBay. He can bid.
Google the titles, you can often find them for sale via Amazon or Abebooks, with prices reflecting value placed on them by those who buy them.
I've seen copies of books that I actually designed, layed out, did artwork for, etc, going for quite amazing amounts of money.
Here's one I did from the original manuscript: http://www.amazon.co.uk/Operation-Paraquat-Battle-South-Georgia/dp/0948251131
A 'new' copy currently offered for £170, average £30. Mine's signed by Roger, the author, and I get a thank-you in the credits, which is nice! 😀
Take them to an old book dealer, see what they think they're worth? Put them on eBay with that as a reserve, if it doesn't make reserve, sell them to him for that?
cheers guys. book dealers not so handy round here. but you're right, quite startling amounts (in £10s, but still way more than I'd have thought) for old books :(()