Another site worth checking out is BookScouter, which will check the selling price on 55 different vendors. The list will include the offer price, how they pay (Paypal, check, etc.) as well as whether they pay for shipping and under what terms. If you have a lot of books to sell, they can search up to 3000 ISBNs in a single request if you upgrade to BookScouter Pro. There is also historical prices too in case you want to review trends.
Whether you have a website or are still dreaming up ideas for a blog, you can also look into affiliate marketing. With affiliate marketing, you partner with brands and businesses within the content of your website. If you mention a product or service, you link to that produce or service using a unique affiliate code you received when you signed up for that particular affiliate program. From there, you’ll make money any time someone buys a product or service through your link.