1

Info on the Mainz card (in German only, use google translate): http://www.touristik-mainz.de/mainzcard.html. The card is good for transport in Mainz and Wiesbaden only, not on the S-Bahn from Mainz to the airport.. Birkenstrasse is way out of the city center. Day ticket for trams and busses in Mainz and Wiesbaden is € 5.90 per person, € 8.80 for up to 5 persons. These can be bought from one of the ticket machines at the tram stop in front of the station and may have to be validated when you board the tram. Check if there is a date and time printed on them. To get from Birkenstrasse to the airport, you should be able to buy a ticket at the Birkenstrasse tram stop for € 4.10 per person, directly before departure. This is good for the tram and the S-Bahn.

2

I suppose you have friends at Birkenstrasse. Otherwise it would be easier to sleep in one of the hotels in front of the railway station which offer very often highly discounted room rates.
http://www.booking.com/

3

Look here http://www.mvg-mainz.de/tickets-tarife/fuer-touristen-und-ausfluegler.html

Mainz day ticket is 5,90 Euro pP. Does not help to bring you to FRA airport the next day as the ticket is issued per calendar day and the airport is in another tariff structure.

4

English information is available here: http://www.rmv.de/en/

RMV is the regional public transporation thing.

One way ride per person would be around 4,15 €.

When you enter the information in the form just choose "Mainz Hauptbahnhof" and arrive at "Frankfurt Flughafen Regionalbahnhof" or "Frankfurt Flughafen Fernbahnhof". That only applies if you are flying out of the international airport. Frankfurt Hahn is actually not in Frankfurt and you will only be able to access it via the corresponding transport (check out airport Hahn page) or expensive on and off desaster travel which you want to avoid.

It is not possible to get a ticket for the tram and the train to the airport together, however, all ticket machines can be switched to English and also the people around are in general very helpful if you ask them to assist you in book a ticket.

Depening on what time of the day you arrive in Mainz, a group ticket makes sense if you are at least 2 people and want to check out more than 1 place in Mainz - I assume the cost would be something around 10 €.

Where you can get tickets:

• for the ticket to the airport: in the central station - machines available in English as well
• for getting around Mainz, at every station there will be machines available.

The bus will need around 70 min between Hahn and Mainz. The shuttle does not operate 24 hrs, so maybe you want to supply us with your detailled travel times so we can go ahead with recommendations?