Cars under $75,000 that have extraordinary chassis construction:
Alfa Romeo 4C, structural carbon fiber tub with an aluminum rear section BMW i3, carbon fiber body on an aluminum chassis Corvette, SMC body on an aluminum chassis Lotus Evora, SMC body on an aluminum chassis
Of course the modern aluminum chassis is most likely to be that of rectangular tubes with the cross sections turned tall-wise. That method of construction increases stiffness and mitigates the effect of stress cycles on aluminum.