I want to buy a tablet and i have some questions?

So i want to buy a tablet (like a laptop but touch screen) and it would take way to long for me to save up for a new one (about 1,000-3,000) so i was talking to my dad about buying a used one for a lot cheaper. He is worried that if i buy a used one it would be broken or not work well and stuff like that, so my question is how would i be able to know if the person selling had a good quality one and where could i go to get one? I am not allowed to buy off of ebay but i have been looking at some on Craig's list if that helps at all. Thanks