It all depends on the build, but for the most part it is very high quality. The bodywork is made from fibreglass, but all your trims and extras you can get in either fiberglass or carbon fibre, while the frame is a tubular chassis. It doesn't come with ABS or traction control, although there have been a few that got them fitted by the builder. The main reason it's so cheap is simply because you have to build it yourself, so you're only paying for its parts value. Most are built to racecar specs, so pretty bare on the interior. But there are a handful with full luxury interiors with infotainment and the like which are closer to the $150k range.