Have you checked out how much it will cost him 6 months or a year after the test?
I know my insurance quotes for the same car dropped from £1400 to £800 in the first 6 months. Although I was 32, I don’t know if the same happens at 18. Made way more difference than that amount of time of no-claims bonus.
Missing 6 months of driving only means missing this winter, plus as an added bonus you don’t have the worry of a new driver driving in ice and snow.
Again I’m old, but pass plus seemed to make absolutely no difference to quotes at my age, even when I’d just passed – the cheapest quotes all ignored it.
Oh and I found third party no cheaper than comprehensive (some companies even quote it higher for some crazy reason). With a cheap car and a new driver, the big risk is that you write off someone elses expensive car, or injure someone else badly, so the comprehensive bit is a tiny risk in proportion to the damage you could do to others.
In terms of how people get kids added to their policies and only pay £700 or whatever, it is probably that they have an existing car and add the kid onto that as a named driver, which makes it plausible that the kid is actually not the main driver, whereas if you sign up for a whole new policy with a kid as a named driver, they probably assume you’ve actually bought the car for the kid and are just telling lies about who will drive it most.
Joe