Really not sure what I need to be looking for. If I was buying a sub for a vehicle I would not even consider a 15. I have considered CT Sounds Bio car audio subs. These are low end subs but still think they are a big upgrade over a $100-$200 prefab sub box setup. 12" is $25 while the 15" is $60 both could be had for slightly cheaper and this is shipped. Amps I am looking at is the 100w and 250w Dayton plate amps. Sealed or Ported I am not sure. As for speakers I have low end polk speakers. Also need a receiver and center at this point. This is a spring/summer project.