No it will not damage sub unless its raining or something.
you would need multiple amplifiers if you were using 1000 wats of subs. two amps one on each sub should work decently.
YES
200 watts
its the same year round
One can purchase car speakers and sub woofers from most car accessories stores including Halfords. They can also be purchased online at Argos and Amazon.
No, but it is nice if you want to play loud music.
no they are called accustomass moduals and their way better
In the back pointing at back hatch
Automobile speakers and sub-woofers (loudspeakers) are not that difficult to locate. Some box stores like Walmart and Best Buy carry a good range of automobile speakers and sub-woofers.
ground it to the body of the car floor board
yes ,if you want to have it insured when it gets stolen