The cost of a smart home for an elderly person can vary depending on the specific equipment and devices that are chosen. Some basic equipment, such as a smart lock or security camera, may cost a few hundred dollars, while a more comprehensive smart home system with multiple devices could cost several thousand dollars. It's also important to consider any ongoing costs, such as monthly fees for cloud storage or subscription services. It's best to research and compare the costs of different equipment options to find the best fit for your budget and the needs of the elderly person.