Is $1,300 to fix a minor roof leak a fair price?

My house is a Victorian terraced house in the north of England. I recently moved in and did not budget for a major overhaul so soon. I have old photos from 1.5 years ago showing the dormers looked the same, implying they aren't rapidly deteriorating. A letting agent who managed the property before I bought it said the house was never a problem. I am concerned about the risks of leaving the dormers for another 2 or 3 years. I am also intending to enhance the loft insulation under the Great British Insulation Scheme and wonder if the dormer condition could affect this.