General power from overseas pakistani for property

Salam to all,

Kindly help me i want to buy property from overseas pakistani, he is living in london and the property is in karachi,

If i given general power and make it from karachi while deliver to seller for signature and attestation and overseas (seller) cnic is expire and for renewal the time was expand 6 weeks from the date of applying

My question is that i want to make documents and submit to seller at london and for signature so what is problems i will face

If and problem is coming during process then guide me about the problems and solution

I am upset in this condition kindly anyone guide me and help me please

What is the solution or alternate documents in place of expire cnic

Its urgent please reply me as soon as possible


Thanks,

Fatima ali