India, Dec. 26 -- With GRAP measures becoming a near-annual reality in Delhi, many petrol and diesel car owners are beginning to reassess long-term ownership. Each winter, worsening air quality leads to restrictions under the Graded Response Action Plan, and vehicles are often the first to face curbs.

GRAP has four stages, with Stage III and IV being the most disruptive. Under Stage III, BS3 petrol and BS4 diesel vehicles are barred from operating across Delhi-NCR. BS4 petrol cars are technically allowed, but recent enforcement has restricted out-of-state BS4 petrol vehicles from entering Delhi. This has added to the confusion for owners who believed petrol cars were relatively safer from bans.

BS6 vehicles, which have been mandatory si...