The guide price has been calculated by using a traffic estimator and comparing the estimated CPC and daily cost of the keyword phrase "home insurance quote" with two similar keyword phrases "insurance quote" and "home insurance".
Strange...
From the time of the original post right up until earlier today the phrase "home insurance quote" was returning 18,100 for local using the Traffic Estimator tool.
Now I also see the same figures as you post.
What could have happened there?
Estimated average CPC is £16.88 and estimated daily cost is £45.31
I've decided to keep hold of this one, the phrase returns a good amount of ads. and will look at developing it instead.