A lot of money ( time) is spent on doing things to the engine that aren't allowed and then covering them up. If builders that are charging the ridiculous prices they are wouldn't be doing this kind of thing, the prices wouldn't be as bad. Look at it this way. If a person can purchase a kit engine from who ever for around 300 dollars what all do you think is being done to it that is adding the higher cost? Pipe and exhaust. 100 dollars. Now you are at 400 dollars. You know as well as I do that the so called kit engine you and I would purchase is less than 300 dollars to the big builders. So for poops and giggles lets take it back to 300 dollars with the pipe. Also consider this. Purchasing in large lots gives even a larger price break. So lets take another 100 dollars off that. Now, Big builders have lights, machines, employees, overhead, insurance on building, insurance on employees, maintenance, heat. With that being said, do you feel that it justifies the LARGE prices that are out there? People are creatures of habit. If their competitor has that big dollar engine then they need it also. If they think that just because it was built by a big name karter who won a national championship here and there, then he MUST build the best!!! What is common sense? Common sense is developed not something you are born with.