Register your phones at donotcall.gov. It might help, I'm registered, but still get a scam call at times.

"What is the purpose of this call" seems to be a great way to cut to the chase. Thanks! I no longer answer calls from unfamiliar numbers, but once in a while it appears to be a local number so I get tricked into answering, and it's often google, yelp or some marketing company trying to sell me advertising.

I usually reply that if they found me on online, then my customers can too, without their help. Of course, this year, I'm not doing any (or much) business anyway, so there is no way I'm paying for advertising.

If a call comes in from an unrecognized number I don't answer. If it's important the caller will leave a message. If the caller's number is masked — 000-000-0000 — my phone doesn't even ring.

Or ask for their FCC permit number. There is no FCC permit number but they will panic.....

My number is also for the b&b. That means I have to answer every call unless my phone identifies it as a scam. I just listen to the intro and click then immediately block that number. Of course then they immediately use another number.

I've been thinking about letting unknown numbers go to voicemail but for some reason I still answer the phone.

My number is a business number, so has to be public, but you can use.
"Soury, none pesson spec Anglish here."
"What colour are your knickers, I will bet they are white ones arn't they ?"
"I am sorry no one is in the office at this time. Click. But if you wish to receive a printed invoice please press two."

I have an app that I can turn off and on. It's a standalone blocker, I use my stock dialer. I can set it to block any number not in my contacts and without ringing sends it to voicemail. I recorded this message: "I don't take calls not on my contact list, leave a message or a text and I'll add you". It works. If they don't message me, they're spam.
[play.google.com]

If they are soliciting money, for example "police union", by Federal Law they Must tell you what pencentage/how much of your donation will actually be used for the stated purpose IF you ask....(hint: about .02 on the dollar!)
I cheerily tell them i am prepared to buy/donate if they can tell me this amount.....and am met with a dial tone or mealy-mouth.
The most interesting was a guy selling a year's subscription to Time Magazine,for some worth cause which i forget...well over $120 even years ago....silence when I asked, then in a teeny, tiny voice,he said $2.63..........

I solve this with caller ID and don't answer numbers I don't know. Much less aggravating