The great thing about this proven method is that there is a huge profit margin, and this idea cannot become saturated anytime soon. I discovered this little gem after I sold all three of my used college textbooks all in less than four days on Amazon! A couple of them I could not get that much money for because of competing prices, but I did sell one for $40. My previous goal was to get at least a 60% or more turnaround on my profits, and to avoid buying in bulk (for now). My goal has been accomplished thanks to college students. This method works best before college semesters start. What I do is go on CL and search for college textbooks under the "books" section. There are an incredible amount of textbooks listed before semesters begin, and for insanely cheap prices! If the price is no more than about $50, then I will search on Amazon for the book; if the book does not exist, or I can make a profit beating the lowest price, then I purchase it. I have found textbooks as low as $20 on CL, and on Amazon the lowest price for the "used" textbook is around $80! The great thing about this method is that you can repeat this with every city and state on CL, and pay cheap prices for shipping. Media Mail only costs $3, and will not hurt your bottom-line. If this technique ever got saturated for any reason, then you could go to your local community college or university and look on their bulletin boards for cheap textbooks. If you decide to visit campus's, put up your own "cheap textbooks wanted" flier to increase your income. I will edit this thread if I have another idea to add.