Google voice has been around for like 15 years. It's your perm number, that your direct calls to your real number as you like/don't like.
Personally I give out work number that is semi permanent and fam/friends get GV #. I use one message app for work # and one for GV. Allows me to pay attention/prioritize during work/personal time.
Been doing this for more than 12 years. 8 employers, no worries.
You must use your Google voice phone number often enough for them not to disable it. I had a Google voice number. Used it infrequently. They disabled it.
Yep, dual sim is a thing. However, my employer wants full control of the phone so they provided an iPhone. (I'm an Android user) The biggest pro of 2 phones is that you can silence the work phone outside work hours.
With my 1st temp job ('99) I told my boss that the best feature on the work phone the power button was. The moment I left the building it would be turned off. Alas, those modern phones have a complete sequence to go trough to get them off, so I now use the automated do not desturb. Alas, iPhone has only times you can set daily, instead weekday dependent times. Between 18:00 and 7:00 the thing is quiet, no exceptions.
Yep, when they have control overthe phone, yep. This iPhone tells me it's managed by my organisation so they can do what they want with it, including looking up the location of the device.
Yes. Most modern phones are dual-sim. New Google Pixels, new iPhones, All Xiaomis afaik.
You can give them phone number A and then completely disable that sim out of work hours.
Edit: also you can have "virtual" phone numbers that you just use inside an app on your phone, but they don't do as much as a normal mobile number so I personally wouldn't take my chances.
Depends where you live. MoreMins lets you buy a virtual phone number for about €4/mo if I remember right, which is wayy cheaper than anything physical you can get anything here in Australia.