Definiely you need to READ EVERY WORD BEFORE SIGNING ANYTHING!
Here's the store that "served" me: 3 Digital Wy Ste 2, Maynard, MA 01754
I was told I could get a free apple watch during Thanksgiving promotion, no new line, no monthly fee, and I only need to pay the tax. They then start to charge me activation fee + monthly line fee + monthly device fee.
I talked to the store and they didn't know anything about "free apple watch" and couldn't do anything, and then redirected me to Verizon. Verizon asked me to return the apple watch to the store, and this store said they don't accept the return for apple watch.
I then talked to verizon again, they said they will escalate and someone will reply me in 3~4 days, but no update in 10 days.