Have you considered using a 3D printing service instead of buying your own printer? The accuracy of the prints is much higher and the materials produced by the higher-end printers are strong enough to be used as functional prototypes. The parts are also surprisingly affordable.

For auto parts prototypes I would recommend nylon 12 3D printed with HP Multi Jet Fusion 3D printing technology. This printer has a build volume of 380 x 285 x 380 mm (14.9" x 11.2" x 14.9"), and it is used in auto factories (such as Volkswagen and BMW) to build functional prototypes and manufacture end-use parts.

My go-to 3D printing company is Tempus 3D because they are an HP-certified shop, their prices are very competitive, and the team is passionate about doing quality work. their website is https://www.tempus3d.com/. Examples of nylon 12 used in auto parts can be found in their resources section at https://www.tempus3d.com/news.

Good luck with your builds!