Next, consider what you have to sell. What kinds of materials are commonly donated, in what condition? DVDs, audio cds, ephemera (pamphlets, maps, programs, advertising, etc) can be attractive sale possibilities. As a general rule, current non-fiction sells better than fiction. Clean attractive copies will always sell better than basement refugees. And no one wants old textbooks.
These are only general guidelines, however, and you will find exceptions to every rule. Bestseller fiction can be worth listing if you can get it up quickly. Old textbooks are good only for recycling, but current textbooks and other college course readings are good sellers. Condition isn’t always important to a prospective buyer. A collector on a budget may well be delighted to buy a damaged copy of a costly book when it’s a bargain.
Does your state permit the sale of discarded library books? There are sure to be good titles among them. A happy surprise for me was to discover the acceptability of exlibrary copies in the marketplace. The quantity of discards may be a challenge with a library system of any size. If you aren’t already including them in your public sales, then screening and storage will be issues. You will want to talk with library staff to find a way for you to screen and select the saleable books as part of their regular discarding work flow.
Finally, look at the space you have to work in. The size of your inventory can’t be any larger than your shelves for storage. You’ll want a computer work area, as many bookcases as your room can accommodate, something for flat storage, something to hold supplies, and a good table for wrapping. Ideally, this is a room separate from the general sorting and work area. Your online inventory needs to be secure, each item in its place ready to be retrieved when sold.