Complex sentence: The Alhambra is designed by SEAT, Volkswagen and Ford, that they produce practically the same model (SEAT Alhambra, Ford Galaxy and Volkswagen Sharan) with characteristic similars, but different motors and interiors.
Split into simpler sentences: The Alhambra is designed by SEAT, Volkswagen and Ford. The three manufacturers produce practically the same model (SEAT Alhambra, Ford Galaxy and Volkswagen Sharan) but with different engines and interiors.