Thank you very much for your link and very informative post indeed.
But I still don’t know where to start with. There are a few dealers in Islamabad as well and I am going to contact them today any time soon and would come here again to ask for your suggestion, if this is ok with you.
Sure i’m glad if i can help u along in this regard 
May i suggest that first of all u put all the power consumer together and calculate how many hours/day these appliances will be in need of electric power
Like this (just an example)
3 Ceiling fan á 80w run for 5 hours each = 1200w/h
5 Tubelights á 30w run for 6 hours each = 900w/h
U can add consumers/appliances as per ur requirement
Makes a total 2100w/h
So if u live in ISB/RWP u should know how many hours the sunshine lasts on averge per day at ur specific location. In this regrad just google to find that out
Now as above mentioned need is 2100W/h or 2.1KW/h and the Sunshine lasts around 10 Hours u need Solarpanels which produce atleast 210W so u can use it for 10 hours to get the desired 2100W/h
Now this is only a numerical calculation which won’t be aplicable in the practical life.
Problem is that the useable Sunshine/Radiation is too weak at the Dawn and Dusk to consistently produce 210W in above given example. So better take 10-15% higher capacity just to cover up the loss at those times. Instead 210W take 230W/240W
U may have look here
http://www.alibaba.com/product-gs/205850683/Off_grid_Solar_power_system_for.html
Re: Pakistan and its electricity crises? how to solve it
Thanks for your concern.
I had a chat with two dealers in ISB yesterday for 1000W of solar power. One of them come up with Rs270000, also telling the Rs500 cost per cell, the cheapest out of the two but unfortunately I couldn't get technical details as the person I spoke to was a receptionist and the boss was out.
Now as you mentioned above if my need is 2100W/h or 2.1KW/h and the Sunshine lasts around 10 Hours I need Solarpanels which produce atleast 210W so I can use it for 10 hours to get the desired 2100W/h, but as I am going to get a 1000W solar system, it means I would be able to produce, 10kw/h of power to use, as per your suggested calculation? and which solar panel shall I go for; Mono or Poly?
Moreover, I guess we are talking about the power to be used directly from the solar panels where there is no battery bank involved. So, it means the greater the no of batteries the greater the power you can use during the night or blackout.
Re: Pakistan and its electricity crises? how to solve it
^^
Well if u install 1KW Solar Panels that would produce at best 8KW/h as the Dawnand Dusk hours won't produce exactly 1KW/h becoz of low Sun radiation
During the night hours u'll need some sort of battery Bank to get the power produced during day light stored.
Means u'll need probably Ceiling/Pedastel Fans and possibly a Refridgerator + 1-2 lights during the night hours.
So better calculate the power consumption for that Time and this'll help to set-up the Battery bank for the nights
For the Daylight u'll also need to that very calculation coz if for example u'll be in need of 6KW/h during daylight and u need for example 3.5KW/h during night hours then the Solar Panels need to produce a total of 9.5KW/h - 10KW/h during the sun radiation hours
One thing is very important to keep notice of/in mind ..... even during day light/sun radiation hours a 1KW/h doesn't produce exactly 1KW/h or not even 90% if it's not aligned/directed properply ....... U may've seen some motorised Satellite dishes ...... These systems r used to move the dish from Satellite to satellite without going upstairs/on the roof and doing it manualy ..... these motorised system can be set up to follow a certain arc on the horizon ..... similar is the case with sun ..... since the Sunrise for u is in the southeast and Sunset in the southwest it'll be the best solution to use such a Set up (originally meant for Big Sat dishes) ..... this would result in producing at 90% or even higher during the Sun radiation period and the higher electricity output would break even ur investment very soon
I would recommend the Mono as their effeciency is higher + longer life span