In article , says...
Just wondering if this has happened to anyone else...

Two weeks before our double glazing is due to be installed they've just told
us that they can't actually do it for the price that we signed a contract
for 2 months ago. They're now saying that they need an extra £746 to dothe
job. The reason being for something that they openly admit to having not
costed up.

Technically I think you could get another company to do the work and sue
the original contractor for "loss of bargain" to get the difference in
prices, but it's really one for the legal groups. Maybe if you suggest
to the original contractor that that's what you might do then they might
honour the original price - if they do then just make sure that they do
the job properly or it could drag on for ages.