According to engineer, the only suitable place for the satellite dish was on the left gable wall ( no longer it seems fix them to chimneys, which would have been more suitable option) - we just have to hope that next doors' landlord is happy with install overhanging his driveway, although fixed to our gable wall.
All up and running ok...
After spending a week watching TV on a small portable TV with only terrestrial channels 1-5, having option of 500+ channels is a real luxury!