Regarding my car, the situation has now been settled, and in good time.
Central London Lofts were very responsive and sincere, and we are not out of pocket. In fact, along with a generous settlement we received a personal visit from Barry, a manager at CLL, hand delivering wine and flowers and an apology (even though at this stage it was not clear that CLL were directly to blame for the accident).
When we first saw him, on the day of the incident, Barry was genuinely upset and affected by what had happened - he clearly cares about the safety of his builders, and he was quick to attend the scene and deal with the aftermath. And as I mentioned above, resolved completely to my satisfaction.