Do scammers still try to get "local-seeming" numbers? Any mechanisms to prevent them registering, using stolen credit card numbers?

I have monitoring in place for such behaviour, also detection for too many calls under specific amount of time with locations. I am still very new to actually have scamers finding the website I think.

Scammers have ways to spoof numbers. I doubt they will bother buying numbers unless they can get a bunch of them.