If it is of any help I have a great deal of experience with completing loft conversions. I have bought and rented out or refurbished and extended for sale numerous houses in Wandsworth over the last few years. I use a team who primarily work in the SW/ Wandsworth area but they have travelled further before for some of my projects ( not sure exactly where you are!). It is hard to find a good team but I have used Clive and his team for all of my projects including extensions, side returns etc and they have completed the project on time, high standard of workmanship/finish and always answer my calls!! Interestingly their prices are extremely competitive- which is crucial to me as I have to stick to very tight budgets.Good luck with finding a good team but if you are interested their number is 07966 476862.