Basically the score is, by putting on alloys, trick body kits, nice interiors, big ICE systems you're making the car a 'target for thieves', right? We know that, and obviously so do the insurance companies. But the deal is with most insurers, is if you tell them about the 'very few' mods you have (take note mods are only really classed as extras that affect the performance of the car, i.e. exhaust systems, engine chargers etc), the general line will be 'thanks for telling us - we won't put the car 'up a group' (i.e. charge you more), but we also won't cover the extra cost of your alloy wheels/body kit/tasty seats in the event of any claim...' This is fare enough, in other words, if your car goes missing, you get paid out, based on a standard car, minus all the goodies. If YOU DO want all the extras covered, best bet will be try a specialist insurance company who will be alot more friendly and probably offer you a better deal in the long run.