Some wiseacre once said that only death and taxes are certain in this life. Except of course, it's not certain who said it first. Some less patriotic folk claim Daniel Defoe was first out of the starting blocks in 1726, while the true Americans claim it for Benjamin Franklin in 1817. No matter who may have the right of it, the modern reality is that, in these times of greater sexual equality, we should probably add childbirth to the list and ask an insurance actuary to calculate the probability of all such accidents of nature.

Actuaries are, of course, the world's experts on everything connected to accidents. Whenever it comes to risks and perils, they will be there giving you chapter and verse on the odds of it actually happening. For the most part, they focus on the averages. For traffic accidents, this means measuring everything in terms of the standard makes and models of vehicle. When it comes to the individual risks, they can put a price on those as well. In history, for example, we learn that Betty Grable insured her legs for $1 million each. Michael Flatley who jumps around in Riverdance insures his legs for $47 million. One wonders how much his ego is worth.

In all the modifications you can make to your vehicle, there's a basic truth. If you do something to make the vehicle safer to drive, you earn a discount. If you make it more likely to be stolen or damaged, the premium rates go up. So fit better brakes, reinforce the seat belts and add a GPS tracking system to help find the vehicle should it drive away, and you are rewarded. But if what you do is as much about your ego as about the vehicle, then there's likely to be a price to pay. How much extra the insurer will add to the premium depends on how much you spend. Simply adding custom wheels and rims is not expensive and may well be accepted as within the fair market values for the standard models of vehicle. But once you add in expensive tires, tint the windows, crank up the volume on the sound system, mess with the suspension and increase the power output of the engine, you are into an individually priced policy.

The more you modify your vehicle, the greater the need to liaise with the insurance industry. Do not simply get car insurance quotes through this site. You need to give proposed insurers a list of the modifications and agree the value of the vehicle before you firm up on a policy. This is not going to be cheap car insurance. Once you have that acrylic paint job and fit a turbo, you are in a rocket that's costing you a small fortune to insure. Remember this is going to be an obvious vehicle. The police are always going to be interested if your high-profile ride is not insured. Don't take risks. Discuss everything with your insurers before you modify and keep them up to speed if you change any of the specifications.