How to get a phone from Ebay up and running?

I currently have cell phone service with T-Mobile, I have a Motorola V66 which I got as part of signing up for this deal (I got it because it was my first cell phone, and it was free).

Now I would like to upgrade the phone and have seen many phones on ebay.

If I buy a phone from ebay, how do I get it up and running? Do I just put the SIM card from the v66 into the new phone, and presto? Can I actually do that or are SIM cards unique to certain phones

Or is there something more? Thanks!

---

› See More: How to get a phone from Ebay up and running?

you have to make sure the phone is unlocked or if it isnt then it has to be a t-mobile phone, if you put your sim in a phone thats locked in wont read it, th ephone MUST be UNLOCKED or already t-mobile branded. once it meets these requirements you can go ahead and pop your sim in there and bam. the only other thing you have to look out for is if the phone's bands will work in america, for that, just type in the forum what phones youre considering and the forum will let ya know more on the phone