You could use Google Voice to filter spam calls. It works verywell for me and international rates are veryt low.rentz wrote:.....
I've been thinking of getting one to make into an ipvoice box to filter out some of these spam phone calls
The Google voice number will cost you a one time fee, you can port your existing number to google voice and route inbound calls to multible phones, e. g. home phone and cell phone. If you use Gmail and Chrome it evrn allows you to answer calls on a PC or tablet.
I use it for inbouns and outbound calls to mask my real cell phone number, it provides web based access to voicemails, SMS messages, call logs and the routing features. Be aware that Google is trying to market Google Fi right now but there are/ were some issues.
More details can be found at https://voice.google.com