Recent home insurance increases in some parts of the Illawarra are more than 700 percentage points above the national average.
According to a recent study by Canstar, an independent body that rates financial products such as home insurance, the average national premium rises from 2011 to 2012 are about 20 per cent.
Yet in the case the Mercury uncovered this week, Dorothy Fretus of Warilla found her NRMA Insurance bill had climbed from $843 to $7473, a jump of $6630 or 786 per cent.
According to the Canstar report, the national average increase for a home insured for $500,000 was 24 per cent. If the contents were insured for $150,000, the national average rise was 34 per cent.
By either measure, Mrs Fretus's premiums are a long, long way above the national average.
Like an increasing number of NRMA customers in the area, Mrs Fretus has taken her business elsewhere and received a much better rate.
Canstar research manager Chris Groth said the organisation had seen quite big differences in policy premiums but nothing of the magnitude Wollongong NRMA customers had experienced.
He said many of the big jumps that Canstar had seen were the result of companies pricing in flood cover to policies that had not previously had it.
As customers exiting NRMA Insurance have found, policy rates can vary substantially. Mr Groth said this was not unusual.
He said insurers used different "pricing engines", which were a method of calculating how much to charge.
"Some are quite a bit more advanced than others. Some companies quote at a postcode or a suburb level whereas others are a little bit more sophisticated and might quote down to a street level or address level", Mr Groth said.
"In some suburbs you might find someone saying, 'But I live up on the hill, and I'm getting the same price as someone living down next to the creek'.
"That would be because the insurance company is putting the same risk factors over everyone in that postcode or suburb.
"But some other companies will recognise that one's not in a flood risk area where the other person in the same suburb is and they'll price those two people differently."
Mr Groth suggested that people check several insurers to get the best price and appropriate cover.
"Reading the details of the inclusions in the policy and removing those you don't need can help reduce the cost," he said.