We need the whole house to be re-windowed. It's a 4 bedroom, two reception and includes 2 big bays and 2 sets of French doors so it's a pretty big job.
We have had 2 quotes so far - one was £21k inc vat, the other was £9k plus vat (so about £12k in total). Both are FENSA accredited but I ws a bot shocked at the difference in price 
Can anyone give a vague idea of what I should expect to be paying ? also any recommendations of good companies? we are in North London. Thanks.