Fellow tsikoteers, need help on where to find some accessories for my '08 Vios. Yung same na binebenta sa casa in terms of quality.

1. Luggage Tray (1,4++ sa Otis) Meron pa bang mapagkukunan na mas mura pero same sa binebenta nila?

2. Back Sensor (4k+ two sensors, 6k+ four sensors sa Otis pa rin)

I was wondering if having back sensors installed outside casa will void the warranty? And for those who have back sensors on their vios, meron na bang wiring na nakaabang for sensors? TIA!