bobholder

Hi folks. I,m new and I don't know if I'm in the right place. I have a 2002 Sequoia I want to put a hitch on. Can I use a simple wiring plug that takes the 4 outputs from the vehicle (left turn, right turn, brake lights and tail lights) and puts them on a flat 4 connector? I saw a $60 plug that isolates the trailer lights from the vehicle. It gets its power directly from the battery. Sounds great but it turns a $20 job into a $60 job and I don't know if it's necessary. Any insight is appreciated.