I can't recommend any firm but would advise you to steer clear of Classic Lofts (based in East Dulwich).

Customer service was terrible, staff were rude and unhelpful, several jobs were botched and had to be rectified and they tried to add extras onto the bill at the end.

I think perhaps they are used to dealing with compliant customers who simply hand over cheques without asking any questions. When we queried why they did things in a certain way (that we considered to be corner cutting) it did not go down well.

Given that we were paying a large sum of money for them to do the job for us, we considered this to be unacceptable and they rapidly lost interest three quarters of the way through the job.