the only way I know is to use a repuable broker and if you can get a parent with a full licence
this helps lessen the cost but it a will still be costly expense
you can use the internet sites and get an idea of what costs you are going to be
I priced the insurance for my daughter a few years ago both for full and learner driver insurance and a few rates i got was for a �1000 but eventually got one for �450
and the only reason we got it for that price was because I was on the insurance as a named driver