Student lodging is a great way to save money on hotel fees. We send out periodic emails encouraging students to take in a student if they can, so the ones who sign up for it are generally very accommodating. It's all voluntary, so staying with a host is a great option to take advantage of.
As far as interviews go, I'd say that ours is very similar to Minnesota. It's probably a common theme across the Midwest/B1G. We have two interviews, one student one faculty, that are pretty laid back, conversational interviews. They're metric blind, so numbers aren't even a part of the interview process. There aren't any ethics questions or anything like that, just questions to get to know what kind of person is behind the application.
Also, admissions meetings are held every two weeks, so if you can delay your interview date even just two weeks for a cheaper ticket, there's no real harm in doing so. You'll still make it into the same admissions meeting, or at least the subsequent one.