I have a FreePBX instance hosted with freepbxhosting.com. The external calls have perfect voice quality, but when we internally call each other via our extension numbers, the voice quality of the calls are quite choppy. You can hear everything the speaker is saying, but it has this annoying noise to it. Source: almost 2 years ago

If you host your server at cyberlynk with freepbxhosting.com you can get the modules necessary for Yealink EPM included, or you can host through Clearly IP (It's still at cyberlynk). I do recommend hosting as it tends to be a lot easier and the built in firewall is quite robust. And it eliminates any of the routing headache that comes from having the appliance behind your firewall. Source: about 3 years ago

There's Burner (https://burnerapp.com) and I'm sure there are at least a handful others around. - Source: Hacker News / 9 months ago

There are companies that will let you have a virtual mobile number. 160.com.au is one such provider. There are also "burner" apps that will allocate you a mobile number and send the sms through their app. burnerapp.com is an example. I believe both of these providers can be trusted. Source: over 1 year ago