In Rawalpindi i can recommend sound valley in saddar , he does a clean and reliable install ...
What you should do is visit saddar Rawalpindi, there are a lot of such shops near kamran market, try to visit 5-6 shops tell them the budget and what you are looking for.... note down all prices that they mention.
For example if they quote, pioneer woofer , amp and speakers .. ask them how much kenwood stuff cost in this price bracket. after 3,4 shop you will get an idea of market rate....
Note down the shop name and prices, and compare them later.
What I do if i'm buying something after discussing price etc , and just before install , I would tell them to plug it in and show me the demo, any decent shop would gladly plug in the product and give you a demo in shop, for example if its an lcd I would check bluetooth, usb,aux,wifi before they open up my car