I have looked at some of the 4 bed detached with cons that I do, and they are well under priced.
I do the same kind of house on recently acquired work charging 50% more for the same amount of windows.
I was doing an estate of 4 bed Redrowe houses, leaded fronts with square bays, and charging them £10 including the con.
I dumped the lot because I would have had to increase the price by at least £6 to make them viable, and I knew they wouldn't stand it.
Now they are probably paying the right price to the new cleaner, but there is no way they would have paid it to me, and there's no way they are getting a better service than I gave them.