The answer to 'what size fuse box do I need' is that the size of your fuse box (also called a service panel or circuit breaker panel) depends on the total electrical load and number of circuits in your home. Most homes today require a 200-amp service panel to handle modern electrical needs, but older homes may have smaller 100-amp or 150-amp panels.
The size of your fuse box should be based on the total electrical load, which includes all the lights, appliances, and other devices in your home. As a general guideline, a 200-amp panel can typically handle a home up to 3,000 square feet, while a 100-amp panel is suitable for smaller homes under 1,500 square feet. If you have an older home or are unsure, it's best to consult a licensed electrician who can assess your specific electrical needs and recommend the appropriate fuse box size.