Wi-Fi range will vary depending on many factors in your environment including the material of your walls, how close you are to your neighbors and how many other wireless networks are in your area.  The SURFboard mAX system is designed to provide coverage up to 5,500 sq ft with two nodes, so in general, you can place the SURFboard mAX router in areas of your house where you spend most of your time and the system will adjust to provide the best speed.  If you need to cover areas larger than 5,500 sq ft, you may need more than two nodes.  You can purchase one additional satellite to expand coverage up to 7,500 sq ft.