House Extension Builder Recommendation

Hi,

I am in the process of buying a house and also plan to add a small extension to the rear. The house has an L shaped kitchen/dining area which I intend to square off by adding a small (approx 4m x 4m) extension. I intend to roof this extension by adding a simple lean to roof following the same pitch as the existing projection to the rear. I will also add 2 rooflights and a set of double doors opening to the rear garden. Also looking at adding an extra radiator.
I would appreciate if anyone could recommend a builder that they may have used on a similar sized extension.
I'm not sure if builders are interested in something this size but hopefully I will get something sorted,

Any help would be much appciated.

Paul