The only downside if you buy electronics with batteries: Buyee strictly enforces a maximum 2 batteries per package rule. So for example a Nintendo Switch would be shipped in 2 package because it has 3 batteries, 1 in the tablet, and 1 in each joycon. Have to plan around that when buying multiple electronics https://faq.buyee.jp/article/99?lang=en
Of course buying old stuff requires some ability to do simple repairs. That’s part of the fun.