I would like to talk about a pleasant experience I had when buying online.
It was two years ago. My son had started studying music instrument, the battery. His teacher said me that he had to study every day at home. I checked the prices for a new battery and there were expensive. At that moment I was not sure how long would be the musical career of my son. So far I didn't want to spend so much money in a the instrument. I looked for a second hand one. In the app wallapop I found a battery of another student for a modest price. The trade was easy and the battery was in a good conditions.