Checks bt sockets at home?

BT have to fix the line to your house, and the first socket to which this line is connected. After that, anyone can wire in sockets. If I remember correctly, you can put as many sockets in as you like, but if you plug in more than 4 phones you'll have problems. Therse days, you can buy a phone set that has one base phone, and up to 3 wireless handsets, and these are a lot more convenient to use