If recent posts on the subject, and my memory, are good enough, you can activate the Minis online, through TiVo's website, without ever hooking them up, or talking to anybody.
You just go to activation, type in the TSNs, and they should then show on your account as lifetime service, no fees required.
If I am wrong, I welcome a correction. I just realized, that with all TiVo products I have ever seen, the TSN is on the outside of the box, which somebody could write down, put on their account, and leave the person who buys that product, with that TSN, pretty much screwed. Am I missing something here?