Train itinerary help and suggestions

Better than a rail pass is local day passes.

Day 1) Arrive in Munich Airport to take the local train to reach the hotel.

This is a Munich S-bahn. Buy a day pass at the airport. Then you will have transport throughout the city for the day. Cost is 24.30 EUR for your group of 3.

Day 2) Plan to Visit for neuschwanstein castle, Back to Munich

Buy a Bayern Ticket day pass. Includes bus from Fuessen station to the castle.

Day 3) Plan to visit Zugzpitze, Back to Munich

Buy a Bayern Ticket day pass. May be a less expensive version for this trip.

Day 4) Plan to Visit Salzburg, Back to Munich

Buy a Bayern Ticket day pass. May be a less expensive version for this trip.

Day 5) Local Sightseeing in Munich

Buy an MVV group day pass. 12.80 EUR for the inner district only, or 16.10 EUR for the "XXL" inner plus part of the outer district, example: to Dachau.

Day 6) Travel to Vienna, Austria

You already looked at this on another thread.

The Bayern Ticket costs 25 EUR for the first person and 6 EUR for the 2nd person, The 12 yo rides with you free. Good beginning 9 am weekdays, any time weekends. Buy out of a vending machine at the station (has English language option), or pay 2 EUR more from the ticket window. Good until 3 am the next day for all travel, including Munich city transit. For Salzburg, make sure to ride only Meridian trains as the ticket is not valid on RJ and EC long distance trains.

Day 7), 8) Local Sightseeing in Vienna and and and around Austria and if possible day trip to Budapest

Its 2 1/2 hours to Budapest. Buy an advance ticket if you definitely want to do this. Look at buying just one way, because the return ticket bought in Budapest is a lot cheaper paying in Forints.

Day 9) Travel to Prague, Stay in Prague

You can use the Regiojet train that has cheap anytime prices.

Day 10) Local sightseeing in Prague

Day 11) Back to Munich for a Night stay

Buy the ticket in Prague, as the train is a lot cheaper bought in Koruna.

You show no travel in Germany that can't be done cheaper with other tickets than with a German Rail Pass.

There is no substitute for pricing the segments separately to see how the total compares to a pass. www.seat61.com will help you with advice but it genuinely is a DIY necessity.