score:6
I'm form Croatia and know a bit about this region so here goes (you didn't mention Croatia for your itinerary but I would suggest you visit our coast; I'm presuming you are traveling in the summer time):
You will need from 13 to 20 euros a night for a bed in a dorm in a hostel.
It is widespread in larger cities but it depends on what season it is. A lot of people go to the seaside and are not available for CS then.
Depending on how many of you are in a travel group, you would need about 20-40 euros a day for two self-prepared meals (pasta with some sauces or something) for 4-5 people.
For traveling locally, you almost never need a reservation but if you are traveling internationally, you will always need to book a seat or berth in a train.
25 euros and up...
Perhaps budget for visiting museums, monuments, drinking, partying. Everything is more expensive in summer time and drinks are from 1.5 to 3 euros for half a liter of beer in a bar and from 3 to 5 euros for a 0.25 L bottle of beer in clubs...
I would suggest taking 1200 to 1500 euros per person for a months travel, including sleeping, eating, monuments and late night drinking every couple of days...
Upvote:3
Subquestion 4. - Train reservations:
I took several trains in Eastern Europe last year including some international ones. I never made any reservations for day time seats. I took a few night trains in the Ukraine and from Bulgaria to Turkey. For these I bought the tickets for the berth the day before.
I did not have an interrail pass, and I think you have to pay extra for a berth on a night train with your pass.
In general I think there are not as many 'super fast trains' in Eastern Europe as in the west.
Here's a good list of international trains that require a reservation.
Upvote:3
Poland: