29.Become a member of their loyalty program.
A loyalty program will be available at many secondhand businesses. Every time you shop there, you can accumulate stamps, which will add up to a future discount. At some places, you can even save up to 50% on your whole order if you shop a particular number of times. Remember to do your research before going to the store, search through their official social media or simply ask the staff before making your purchase.
Occasionally, privately operated thrift stores could provide their own app. But in most cases, you are getting the old-school cardboard punch cards. If you're saving up for a bigger buy, this can be worth it, depending on how much you shop there. Make sure you know people who store up their punch cards throughout the spring and summer to take advantage of the sale pricing when it comes time to purchase their children's back-to-school supplies.