When considering skylight replacement, it’s crucial to review several factors. Start by assessing the age and condition of the existing skylight and flashing to determine if they require immediate attention. Next, examine the overall condition and identify any issues that may affect the new installation's water tightness. Additionally, decide between double or triple glazing based on your energy efficiency needs, and choose the right type of glass such as low E, argon-filled, laminate, or opaque that meets both aesthetic and functional requirements. Finally, ensure the new skylight’s size aligns with your space and lighting, and be aware of any insurance replacement requirements from your provider (if it is an insurance claim).