The answer to 'best leak repair' is to identify and address the root cause of the leak. This often involves inspecting the roof, finding the source of the leak, and making the necessary repairs. The best approach will depend on the type and location of the leak, as well as the condition of the roofing materials.
For small leaks, a temporary sealant or patch may be sufficient. However, for more extensive or recurring leaks, it's often best to have a professional roofing contractor inspect the roof and provide a comprehensive solution. They can identify the underlying issue, such as damaged shingles, flashing, or ventilation problems, and make the necessary repairs to prevent future leaks.