They are usually kits. You have to supply motor, ESC, batteries, radio / transmitter. Will need a decent set of RC tools as well. These aren't "toy grade" rc cars... you can spend well over $1000. There are some RTR kits or ready to race kits but the parts / durability usually aren't that great.Build? They don't come assembled? Do you have to buy a kit and individual pieces?
It is an addictive hobby. Seriously, it is like crack. The engineering and tech in the cars is amazing. My race cars are 2wd / 4wd. Oil filled shocks, three diffs. You learn a lot about how cars are setup for optimal performance (camber, toe, diffs, roll center, etc). Really an amazing hobby.I am not into the RC thing but holly hell that was an amazing video. Made me want one...like I am searching stuff now...LOL.