Inspecting each item before buying is an essential part of your shopping experience not to end up with damaged stuff. For example, if you want to buy a battery-powered device, remember to always have batteries with you to test it out.
If a product is electricity-powered, ask the seller to lead you to the nearest power outlet to check if it’s working properly.
The same goes for clothes, shoes, hats, and similar things. Although, these will require some extra attention for details since they could have hard-to-spot defects. In general, keep an eye out for missing buttons, stains, loose threads, etc.
As for when you're shopping for dishes or glasses, carefully run your thumb around their edges to ensure they’re free from nicks. If these are sold in sets, make sure to count all the items that come together.
Larger items, like pieces of furniture, should also be thoroughly inspected for torn fabric, stains, and stuff like that. Plus, you should measure the furniture to be certain that it’ll fit comfortably in whatever room you want to put it in.
Of course, it’s always a great idea to ask the seller about the condition of their products and how long they’ve had them. This should keep you well-informed and ready to make a clear decision about purchasing said items.