first theres the alternative energy thread for your queries related to this matter.
for solar panel canadian solar panel 300 watt mono crystalline will set you back 30,000 rs.
chinese panels will cost lesser. poly crystalline (less efficient) will be cheaper.
nizam energy is based in karachi, has extensive setup but is also expensive.
solar is not at all cheap, mind you.
to get the most benefit of a solar system, you will need a hybrid inverter. this inverter has capability to charge battery through kelectric or solar. also in day time, it will run load on solar according to its capability. the load above capability of the panels would be run through normal electricity.
the best economical inverter of this type is Infini Hybrid inverter (green colored body) 3Kw system which will cost you 1,10,000 from inverex APT, located near saddar karachi.
canadian solar panels are the best available here. there is a company in islamabad called tesla that also make solar panels. but cost is same. canadian solar have 10 year warranty. tesla gives only 2 year warranty.