There are a great many factors involved in the pricing of roof repairs. These include the type of roof, the amount of repair work to be done including the extent of the water damage. As well skylights can add to the cost if they are directly involved in the leak or area of damage.
You may consider trying to repair your roof yourself to save money. But unless you have the expertise of a professional roofer, or it just happens to be a simple and little fix, you definitely want to call your local roofing company. There is just no substitute for their knowledge and craftsmanship when it comes to roofing repairs.