HIC Quoted me £400 6 weeks ago with full blend, suspension, ind. kit and a few other things. Parked on the drive, no security, Fully comp, ability to drive other cars, protected no claims (9yrs), 27yr old male with an SP30 2yrs ago. I believe my postcode is magic though, lol. Last time I checked I was in the lowest band area you could get luckily.
Thing with HIC is they don't charge you for mods (apart from a fee to update the policy) unless it significantly increases power, even then it's never much more than originally quoted.