I would expect nothing but their time. I would have a hotel to go to at night and make sure I had all my meal money. I would offer to take them out and I would accep an offer of dinner if invited. I would never expect to be taken care of, ever.
Time is enough, if you are a real friend!

room and board, i would be willing to contribute money for that. but without room and board, i am on the next flight outta there.

We just hosted my sister's friend and typically we would supply everything, but she is allergic to gluten so she brought over a lot of gluten free snacks/bread that she knew she liked... so it was easier on us. Besides that, her clothes and personal items, and a little bit of spending cash she didn't bring anything else.

Are you going specifically to see them or the country? if so, then i would expect they may put you up if they have space. i would offer to pay for a couple of meals totally, or maybe drinks out if they are playing your "tour guide". if the trip just happens to be where they live, then i'd plan on maybe staying with them the first night if they offer and maybe take them out to dinner in exchange for them giving you the "low down" on cool things to go do and see. Sometimes people LOVE to play tour guide b/c they are so proud of their city. sometimes they hate doing the "touristy" type things, just come out and ask your friend how much time they have to hang!

Everything!

Depends on if they asked you or you invited yourself?

I would at least expect room and board if they invited me.

Food and toiletries, I would provide myself, especially meals for both of us, as payment for the lodging.

I wouldn't expect anything... if I was staying with them that would be enough..

If I took it upon MYSELF to go visit someone (without an invitation) - I wouldn't expect anything from them. I would make my travel arrangements and go. I MAY ask what days/nights would work best to meet up and maybe ask them if they have any recommendations on places to stay and see while I was there. IF I was ACTUALLY INVITED by someone, then I would ask them where I could plan to stay (with them or a nearby hotel) and what we will plan to do so I know how to pack and what to bring.

I would only expect what they had promised. If they promised nothing, then I would expect just that. If they promised a place to stay, I would expect that and nothing else. It would also depend on the closeness of the friend...someone I had known since high school might be a bit different than an occasional acquaintance I had kept in touch with via internet or phone calls.

Hotel, or at least a place to sleep, food, and entertainment