Completely new to karting. We went with a buddy and his 6-year-old son tonight to practice. My son (6) did 3 different practice sessions and fell in love with it. By the 3rd practice session, he really started to have the hang of it. I guess just looking advice to see where to start? I have a few other buddies who's kids race but they are extremely serious with it all. They have multiple chassis, multiple engines etc. I just want to start simple with him. Where is the best place to buy used karts and equipment?