[Ianomed]

So you do not mean for the users to be imported and posts to be attached to their username as before. In this case it could be as simple as copy/pasting each thread's content across to a new thread, not requiring any mod to be written.

As such the cost could be less depending on how many threads there are. I really can't say, it largely depends on what someone would charge for what's basically data entry type work.

If you're talking a very large MSN group with lots of posts and lots of members, then it may be cheaper to have a script written after all, because once written it would arguably import faster, and allow for more detail to be preserved.