I really enjoyed my stay at Julia's place. The room is spacious and is exactly as described and very central. I had access to the kitchen and fridge which was very helpful. Julia is a very accommodating host and her place is sparkling clean. There was no communication difficulty while I don't speak German. You can get local tips from Julia regarding transportation in Munich. I totally recommend Julia's place for solo travellers.
Regarding my experience with DB (German national railway), for a 3-day trip, I only paid EUR 30.20 to DB on my arrival to the Munich airport and I had 3-day ticket for the city as well as airport transportation on both ways.