I've seen people who say they've been insured for sub 2k at 18 on an RS so there must be some companies out there.
You (and quite a few others on here recently) seem to be getting the wrong end of the stick. But seriously, fundamentally wrong...
It's YOUR personal circumstances that dictate your premium. Of course prices vary between companies but
some people on CS seem to think there must be some magical "company X" that will insure all teenagers on hot hatches for peanuts regardless of whether they're a trainee lawyer or the type who like to hang around mcdonalds.
Those that are lucky enough to have affordable (£1300 - £1600 figures get banded around) insurance on a 172/182 at 18/19 without exception will all have the majority of these things in common:
* Good/excellent postcode according to the INSURER not according to you
* No points/no crashes/no courses & 1 or 2 NCB
* No/few mods (certainly not all "max powered" up)
* Employed (ability to pay the excess etc)
* Probably got a 10 - 20% discount for paying in one lump sum
* 3 named drivers, each with clean licenses and more experience (basically a lower risk)
* Relatively low annual mileage
* Reasonably high excess
Now, of course I am not saying EVERYONE in the world who insures an RS at 18/19 has all of the above (because that'd be wrong, clearly there are exceptions) but see how many of those criteria can be met by the 18/19 year olds insuring 172/182s. I bet it's most.