We had an introductory home insurance discount with Zurich. When it ended last month they quoted €490, more than double last year's rate.
I aimed to spend a maximum of 2 hours dealing with this as it's a headache re-typing all the details into confusing website, deal with callbacks, etc. I got online quotes from 6 companies which ranged from €280 to €610.
Called Zurich back, they went down to €460. Called 2 other brokers I know, best offer was €290... with Zurich!
We have car insurance with Axa so said I would chance giving them a call. 10 minutes later had home insurance with Axa for €240, with lower excess and more benefits than Zurich. Axa gave discounts for having car insurance with them, getting online quote before calling, being member of Credit Union, having smoke alarms, having locks on doors... seemed like they were looking for reasons to take money off!
AA were the most expensive by far - their best rate was €610 and they seemed shocked that I had lower offers elsewhere. 123 were not only expensive but annoyingly persistent, calling me back with a higher(!) quote than their 1st one and sending multiple texts/emails even after I had asked to be removed from their list.
Moral of the story is that it's worth a couple of hours to email/call around.