Hi, I'll be opening a thrift store in South Floida in the next few months and I have a few questions about books.
I'm a dealer who shops at thrift stores so any of my recommendations are from the customers perspective.
1. How do we best organize our books?
It depends on how many you have. Unless it is in the thousands I wouldn't bother sorting them at all.
2. Which types of books sell and which should we get rid of?
Get rid of all textbooks, Readers' Digest condensed books, magazines. Pretty much anything that is updated annually (they will usually have a year in the title).
Computer books are almost always out of date by the time people are willing to give them up. The only reliable exception is the O'Reily animal cover books.
Now for some unsolicited advice.
Dealers can be your friends. The plural there is important. Many Thrifts will try to save some labor by selling all to one dealer out the back door. This is a mistake. Very few will give you full wholesale for them and other dealers will not even show up once it is known.
Your best strategy is to keep the stock moving. What you should do is have a three tiered pricing structure where books spend one week on the top tier. They then are moved to the second tier where they stay until they need to move to the third tier in order to make room for books coming in from above.
Tier one pricing should be standard used book wholesale, which is 1/8 to 1/6 of cover price. Or, to make things easy $3.00-$4.00 for hard cover, $1.50-$2.50 for trade sized paperbacks, $1.00 for mass market (pocket sized) paperbacks.
Tier two should be priced at half the tier one price.
Tier three is also known as a dumpster.
Please don't mar the books. The easiest way is to just use the easy pricing structure above. If you must mark them stickers are tolerable (but some of the stickers I've run into use glue that would be good for space shuttle tiles) but a graphite stamp is best.
Are you going to miss out on some collectible books? Yes. But these are 1 in multiple thousands. I can't count the number of times I've seen books worth nothing to $5.00 marked for 20 to 30 times what they were worth. I've seen Harry Potters with torn jackets and board edges worn all the way to the cardboard prided at $10.00. Even with the internet you need a lot of experience to know what the valuable books are. You could easily waste more time in labor looking up every book than you make finding the collectible ones.
Hope this helps.