If you are willing to spend thousands of rupees extra, some agent in Lahore can get it done.
Better visit with the owner and original registration book. As such vehicle is not required. In Islamabad, seller must be present (buyer may be absent, doesn't matter) and the process is very easy. No fee deposit in NBP, the excise office will collect the fees on the counter.
If the car registration date is older than 5 years, no need to be a tax filer. However if it is less than 5 years and you are a filer, please make sure you are on ATL (Active Tax Payer List)
I recently got transferred a car to one of the relatives in Punjab. The seller was with me and we got the stuff done in one day.