We found a way to stop about 99 percent of such things now. We canceled our land line and went totally smart phones. I may get one call a month that is someone I don't know and I just don't answer it. The quietness of no more phone calls is simply amazing now.
That does help but if you have to give your number out you have to give one of your cell phones numbers.
I got rid of my traditional "landline" last summer and subscribed to Magic Jack. I did keep my old landline number ($20 one time charge) so I can keep giving merchants a phone number (with a 2-ring answering machine on it)
Then I put a message on it that has the "SIT" tone followed by a short "pause" and then a short message saying to "please leave a message at the beep"!!
The SIT tone is explained at the following site
http://yourhomenow.com/sit.html
Essentially, having your answering machine play the SIT (Special Information Tone) at the beginning of your recorded message causes *some* "BOTS" to identify the line as "Disconnected" and hang up. Supposedly it doesn't call you again.
It doesn't work on all of the bots but I reduced my "BOT" calls by more than 1/2!!
Humans that call my number don't seem to even notice the tones and still leave a message. Just don't make the "pause" between the SIT and your message too long!
I wanted to keep my original number since I have had it for nearly 20 years. The landline company was charging me nearly $40/month for a basic line with NO long distance, NO caller ID, and NO voice mail,
Magic Jack is a super deal, uses your internet connection, and (if you buy 6 years [first year $35 + $99 for 5 years] it's about $2 per month! If you want to have 911 service connected to it it's $0.70 extra per month
Magic Jack also has free US/CAN long distance, caller ID and voice mail that will send voice messages directly to your email as MP3 audio files. There's also an APP for smart phones that will make it so you can answer the line on any cell phone from anywhere if you're waiting for a particular call.
I now give that number to all the merchants, warranty signups etc and I don't worry that they might give it to a telemarketer. I probably have 5 or 6 voice messages on the answering machine per week now. Before, I was getting multiple bot calls per day.
Cheers,
Rick