If it is superior to the competition, you need to explain how and why. Don’t try to simply tell the market what it wants; that will never end well.
Dealers selling trade-in vehicles can never know for sure how old the gas is or its quality. Fuel degrades as it ages, losing octane and forming gums that can affect how well the engine starts and runs.
Scented sprays are a fast, inexpensive method of masking odor, but carpeting, upholstery, seat belts and headliners trap and hold odor, which is still there when the perfume wears off.