The market value of the land is rs. 100000. per marla. The government
is paying rs. 80000. per marla as compensation.
In theory, the government is supposed to pay the market value of the land and there is a legal process by which you can dispute the price that they offer.
But, the market value of land is not a matter that can be measured with absolute truth by means not reasonably subject to dispute in the way that you can its area or elevation or location. There is generally some room for reasonable people to disagree over what the market value of land really is, in practice.
So, if you are offered rs. 80000 per marla and you think it is really worth 100000, you have to decide if rs. 20000 per marla is worth the time and trouble to fight over, or whether the route of least resistance to simply accept the government offer is a better deal for you.
In addition to the time and trouble involved in the process, you also have to consider whether your evidence that your 14 marla is worth rs. 280,000, in the aggregate, more than the government is offering is solid enough that it would prevail in the legal process.
You need to consider how solid your evidence from an appraiser would be, how much it would cost you to get the appraiser's testimony, and how much time and effort the legal effort would cost you to make that decision.
In U.S. dollars, this is a fight over $3,640, give or take, based upon day to day variation in exchange rates. If I were you, I would not choose to fight the government over a dispute of this amount. But, ultimately, that is an economic and business decision for you to make.