I've just come across this Website www.accountantsquoteme.co.uk and I can't believe how poor the design and concept is. There is an opportunity to challenge value but not by just focussing on price.
By the way, I noticed the title tag on the homepage "Compare Cheap Accountant Quotes to find the Cheapest Accountants Quote - is that really the clients you want to act for? Here's a video that I thought of when thinking of price.
Price is only part of the value equation and this site does nothing to move the professional forward. Try it offering a guarantee that you're the cheapest accountant in the town. Do a mailshot or telemarketing campaign and see what happens.
The other approach is to set you a survey Website which accountants could use to survey their clients, including comments about the price. This could be "sponsored" by your firm so you could invite non-clients to participate! Interested?