Rs. 300 is the Haryana Roadways bus (Non AC) fare from ISBT Kashmiri Gate, Delhi to Chandigarh ISBT 17.
There was no pre-booking of seats. I had to purchase a ticket there only before the journey started.
The ticket counter is in front of the bus parking area at ISBT Kashmiri Gate, Delhi.
Nearest Metro Station: Kashmere Gate metro station