What's your budget? My recommendation is get a dsp and active subwoofer. Both of this are with built in amp. Get the installers to tune to your music listening preferences. After that you can think of upgrading better speakers and soundproofing.

Below 2k cannot. Maybe soundproof you do later. Try the dsp and active subwoofer first.

Price depends on how many layers you want. If for audio, usually 2 layers minimum. I recommend ea audio in ampang. Price is expensive but their workmanship is good. When it comes to car audio, the installer is way more important than the price of the items you pay. Again, this is just my opinion.