It's true that you can get a pretty penny for those DVDs you don't want anymore by selling them online. However, due to the relatively fragile nature of a disc, you have to ensure that your product is properly packaged before you ship it off to the recipient, and unless you use PayPal shipping services with USPS free pickup or you've got the USPS system set up to print your own postage at home, it'll likely be a huge hassle to take a few packages per day to your local post office or shipping center. So, if you'd prefer to get rid of them at a garage sale, here's the method for properly selling your DVDs.
First, decide if you will use "discriminatory prices". No, that doesn't mean you can choose whom to sell your DVDs to, or who will pay you more; it means you price popular movies higher than unpopular or unknown ones. Realize that if you price them all the same, you'll probably get a lot less for some movies than you could -- but you won't have to go to all the work of individually pricing each DVD. It's up to you.
Next, choose how to organize the DVDs. Do you have enough to merit sorting them into categories (like horror, drama, science fiction, children's, etc.)? Do you want to just alphabetize them and call it good? If you aren't selling very many, you can probably get away with just putting them in a box, but people will more likely look through your entire inventory if they have a way to keep track of where they are in their search for desirable DVDs. Alphabetized movies are more appealing, but certainly more work.
Like many second-hand video shops do, you should keep the discs with you to protect them and yourself. Start a file folder with the DVD discs organized in alphabetical order and keep it near your sales table. When a confused customer brings up the DVD case (although hopefully you clearly stated that all DVDs were available at the table!), you can check the title and quickly flip through your collection to find it for them. Make sure you use soft paper or something that will prevent scratches.
When you make the sale, polish the disc in front of the customer so they can see that it has no scratches on the back. This gives you a chance to clearly state your no-returns policy -- generally a given at garage sales, but important to mention when selling DVDs, because many people will be very upset if they return home to find the disc does not play in their computer or DVD player. You may think it's the nice thing to do to offer a return policy, but to do so means you've given customers permission to return to your house.
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