In the late noughties/early onesies I went through this period where I realised I could just buy anything I wanted that wasn't food from Amazon, and it was briefly great. However, they have had a huge problem with counterfeit, poor quality, seconds, and reconditioned goods for a number of years now. If you need thing X you're much better buying it from a specialist retailer, direct from the manufacturer or - depending on what it is - even from eBay, Gumtree (or its US equivalent Craigslist), particularly for used items.
Avoid Amazon like the plague for non-media items.