You need to take into consideration the following to calculate the amount required to buy an option:
(1) market lot for the underlying script (e.g., For NIFTY, it is 50. For Unitech, it is 9000)
(2) value of premium at the selected strike price (This is Rs 10 in the given example)
Taking the above example, total amount required to buy Unitech call for strike price 95 would be (market lot * premium) = (9000 * 10) = 90000 Rs.
- Hitesh