I think about buying a house in Germany (Frankfurt). How can I learn full list of expenses I should pay next at least ~15 years? My friend scares me that there are always hidden problems like central street-pipes replacing for many thousand euros. How to know the truth? Thank you.
As a first step I would talk to a German real estate agent (Immobilienmakler), who will be able to give you an idea of the costs, fees, insurance needed to purchase a property, and who would be able to address your other common concerns. If you are clear in your initial phone call about what your resources, desires and intentions are; you will probably be able to find an agent (even if you have to call a few different offices first) who will be happy to educate you and give you a ballpark figure for common costs.
Another source you might try is looking on German social networks (facebook, reddit, etc) for other young people in the region who have recently gone through the home buying process, and who would be willing to describe their experience to you. I've found that many people are happy to respond to social media posts such as "I am a 28 year old looking to buy a house, what should I expect?"