Second hand products

Hello everyone! I would like to know where you guys buy second hand laptops or phones? My brother and I just love to take them apart and put them together lol And we need to get cheap products to do this! Hope someone can help

I bought second hand thing on eBay.

Yeah i know ebay is good. But I want to have some alternatives. I also have this site but I never tried buying from them yet so maybe someone here has tried it before? Also i have olx.in and amazon...