I need to get a new one and it seems to be hard to find one for what I prefer--which is buy it with cash, set it up myself, no monthly charge required, pay for useage with purchased data/minute cards rather than a credit card.  If it can go dormant for a few months and there are no activation issues upon starting again, all the better.  If I lose data/minutes not used that's OK.  

Tracfone I believe still offers anonymous activation. No need to use credit card.

This is IMHO a case of don't be penny-wise and pound-foolish. If you have a significant other (SO) or dual personal/work phone, get separate hardware. If you have a SO, then throw a bunch of your old phones into a 'junk' drawer along with your burner phone. Divorce is expensive is what I'm saying. That forty or fifty buck difference will seem paltry to the hourly lawyer fees you'll be paying.

best buy sells refurbished IPhone 6s for a great price.  Annual tracfone for cash works well.

Interesting idea -- I've accumulated a lot of defunct cell and smart phones over the years.  Who would assume there was a working one in the bunch.  Hiding in plain sight.

Have a feeling I'm afraid within next 5 years or less they are going to make it next to impossible to get these plans you can pay in cash for without them entering your personal info when purchasing. Compared to the last 5 years ago to today I've noticed how much harder its gotten to do this. Apps are okay but most can always be traced back.  

I've been using burner and google voice app with great success. Having an extra phone can be tricky in terms of keeping it accessible and charged. If discovered it could lead to interesting questions. Nice things with the apps is you can turn off all notifications and indexing  and also put them in privacy mode so they send any potential calls to vm.

I bought a Tracfone at Target for $50 cash, which had a 90 day plan.  A renew for a year is $99.
Totally separate phone with no traceability .  I got a flip phone, which is a texting challenge, but you can buy a smart phone for maybe $75.    Security is my number one priority.
Interesting I keep it in the box with my old technology and no one knows about it.

Renew for a year (well, 360 days) is just $80 using four $20 90-day refills.  Keep accumulating minutes/texts/megabytes due to modest usage, too.  Just don't let it lapse!

Just like the man said - don't let it lapse!  I let it lapse over a month due to inactivity, lost my number.   Had to get a new number, and explain to the POs, new number.   It is PITA.

I got rid of my burner about a year ago and went to an app.  It gives me a second real number and works better for calls and texts than my burner phone did.  I also don't have to try to handle hiding a second phone in the house.  And, best of all, it hides behind a newsreader app on my phone and actually works as a newsreader unless I take a special action to open it.  I don't think I'll ever go back to a burner phone.