Luckily I don't have to worry about it. My cell phone (only phone I have) shows Spam Call when potential scammers call in. Plus no one could ever convince me from a cold call to send them money. A late friend of mine cracked me up when he said he got a scam call saying if they couldn't collect money, immediately of course, they were going to send the police to his house. He said go ahead...send them and hung up.
It's sad that so many gullible people get conned out of their money. Likely many can't afford to lose a dime. I like that AARP has a scam section that lists probably most of them but these scammers seem to be evolving all the time.