Unlocked, inexpensive?

[Guzzler3]

Ok, I've done iOS and Windows phones. I think it 's time to try an Android phone. But there are just so many to choose from, it's information overload! So help me narrow it down...

Things I need.
Unlocked. Gets the newest, cleanest, OS updates on a timely basis, that isn't hamstringed by carriers or anyone else.
~ 5" screen (not to big, not to small)
MicroSD (where my music/photo collection lives)
Excellent navigation GPS/Compass (I'm terrible at directions and live off navigation apps)

Would like to have.
NFC: For once I would like to try contactless payment. But it isn't truly necessary.
Nice lowlight camera (but just a decent camera is OK, I'm not that much into photos oddly enough).

All of this on a budget, would love to be under $100, but I know that might be impossible. Maybe around the $200 range?

But the biggest thing is the OS with a device that will be supported on a timely basis with new updates. I keep hearing about devices that are left behind and never getting timely updates which scares me to death, especially for security/malware/etc. on a very popular operating system.

P.S.
Carrier compatibility: I'm currently on MetroPCS

 

[Guzzler3]

I finally went with the Moto G4+, took two different orders to get the darn thing. First time was from Amazon (refurb), but they sent the Amazon variant with ads. Sent it back. Second time BestBuy (refurb), actually cheaper than Amazon's.

It's going to take me a while to transition from Windows Phone to Android. I like the fact that I can get more apps, but damn I already miss the live tiles (also the resizing the tiles).