Using force will not accelerate your resolution; it will convert a simple recovery of rent into a severe criminal and civil fight where you risk losing the legal standing you currently hold.
Under Section 6 of the Specific Relief Act, 1963, any person who is forcibly dispossessed without due legal process can file a summary suit. The court will only ask two questions: Was he in possession? and Was he removed by force? The court will order you to hand the keys back to him immediately, irrespective of his non-payment of rent.
The police do not have the legal power to evict a tenant or recover rent on your behalf.
While the court will be sympathetic to your age during trial, Section 6 of the Specific Relief Act specifically prevents owners from taking the law into their own hands.
If you want speed and recovery without criminal exposure move an urgent application directing the tenant to deposit all unpaid arrears (3–4 months) and continue paying monthly rent into the court's account during the trial.
If he fails to pay, the court can strike off his defense, allowing you to get a fast-track summary decree for eviction without a long trial.
You have the legal right to sell your property even if a court suit is pending. However, the buyer's rights will be strictly subject to the final outcome of the court case.
You must explicitly state in the sale deed that an eviction suit is pending. Hiding this from a buyer can lead to fraud charges against you.
Finding a buyer who will pay full market value for a commercial shop with a rogue, non-paying tenant inside is difficult. Buyers will demand a massive discount (often 30%–50%) to take on the burden of the ongoing litigation.