1. How many outside telephone lines do you need?
These are the current telephone lines that are connected to your system. There may be a main published number and some “rollover” numbers. You might also know them as line 1, line 2 and line 3, etc. These are the lines that you pay for each month on your telephone bill.
2. How many POTS lines will you need for fax, alarm, credit card, etc?
If you have an outside line that is not connected to your phone system that you use for a fax machine, a credit card machine, a line that is connected to your security system, etc. This is where you need to account for them.