DBF and I only use our cell phones and do not have a land line. We used to get all types of telemarketers calling and since we pay for our calls (or they come out of our minutes) we wanted to put a stop to it.
You can stop telemarketers from calling you cell phones or land lines by going to the National Do Not Call Registry. It takes effect within 72 hours and then if telemarketers call they are violating the law. If I recall correctly, you have to go in every year to update the information, however, they are working towards making it permanent eventually. The website information is below:https://www.donotcall.gov/register/reg.aspx
I did this for our phones and the calls REALLY STOPPED! I hope this helps someone as I know the calls are annoying.