How do I know if a vehicle I purchase from a dealer doesn't have any problems?

I'm looking for a used cargo van. But I'm paranoid that the dealers that have them aren't trustworthy. The meme inside my head says that they'll lie about the history of the vehicle and its potential problems in order to make a profit. The fact that some of these dealers are located in a bad areas like south central etc. and have few if any reviews online doesn't help either. Any advice? Can "dealerships" be trusted? Are there any tell tale signs to look for? I just want a vehicle that I can feel confident about. Thanks for your help. -Blake