Wally World has the iPhone 6S Verizon Prepaid on clearance for $59, some locations as low as $20. YMMV as usual.
Link for reference:
https://www.walmart.com/ip/Verizo…RRkE0s
Brickseek:
https://brickseek.com/walmart-inv…=77715243
Unlock should be 60 days after activation, see here for reference:
https://www.verizon.com/about/con…ing-policy