Collision coverage is limited to the actual cash value of the vehicle, and requires a deductible, which is the amount you'll need to pay before receiving benefits. Higher deductibles lower your premium but increase the amount you must pay out of your own pocket if a loss occurs. Ask yourself how much you would be willing to pay on short notice in order to save on your premium, or talk to your agent.
The main difference between collision and comprehensive coverage comes down to the question of what the driver controls. Collision insurance will cover events within a motorist's control or when another vehicle collides with your car. Comprehensive coverage generally falls under "acts of God or nature," or things that are typically out of your control when driving. These can include events such as a spooked deer, a heavy hailstorm, or a carjacking.
There is a case to be made for getting just comprehensive and not collision insurance, even if your car is not valuable. Comprehensive covers you for a lot more perils than does collision--including, most importantly, against theft. Regardless of the value of your car, having it stolen is a major inconvenience. Even if your car is worth only $2,000 at the time of the theft, and your insurer gives you $1,500, that sum would go a long way in buying yourself a new vehicle. As we discuss in more detail below, comprehensive insurance generally costs no more than $200 per year, so a $1,500 reimbursement would make the coverage valuable.