Well, it depends. Do you want to play bass or guitar. In my eyes it is alot easier to just start both, if possible. But if you want to get basics down go with the guitar, then when you get a bass you will understand alot of techniques. I started with the bass though because i wanted to play the bass, and soo i started playing guitar so i had a good idea of alot of things. So in other words do what u want to do.