I had an excellent time with Petra and her husband. They are super friendly and welcoming. They even drew me a route for a bike trip to Kloster Andechs. Their place is a bit out of downtown but it's a 3 minute walk from the nearest Ubahn so it's not bad at all. The house was really clean and I actually got my own bathroom downstairs which was nice. I would definitely stay with Petra again the next time I'm in Munich!