A recent study in the UK found most people who modify their cars fail to inform their insurance provider, which could lead to a lack of coverage after an accident. Not that some of those body kits don't deserve to be eviscerated by a speeding semi (assuming no human is hurt, of course).
According to the study, one in five drivers admit to changing the look or performance of their cars, but many don't know that in many cases, such changes would require a change in policy. For instance, half of UK drivers believe adding alloy wheels (44%) or tinted windows (47%), and one-third adding a sports exhaust (36%), bodykit or spoiler (30%), would not require such disclosure (note to self: it does). Without a policy adjustment, most insurers won't cover damages to modified parts, but will still cover injuries.
On a side note, among less-intrusive mods, the study found:
· 12% of respondents have name stickers on the front windscreen
· 17% of drivers say they have soft toys on their dashboard
· 16% have an England flag and 44% hang an air freshener
· 4% of drivers hang fuzzy dice on the rear-view mirror.
Car Modifications 'May Invalidate Insurance' [The Scotsman]
Insurance for Amphibians [internal]