I am going to write this in English because being clear in Spanish is difficult for me.  I take Spanish lessons here on italki.  It appears to me that if students enjoy your teaching style it is possible to be a tutor of Spanish and build up a lot of hours of paid teaching.  I have found that I really do not care that much about my teachers´ credentials.  I have found that often the informal tutors teach me in a manner I like better than many of the professional teachers. 

However, I think there are so many informal tutors of Spanish here from countries like Venezuela where wages are extremely low, that it would be difficult to have a lot of students if you charge more than $10 per hour.  Is that enough to live in Germany? I am not sure about that.

One big advantage that you have is that you speak several languages.  As a beginner, I prefer Spanish teachers who can communicate well in English.  I think you could attract students from many different countries because of your ability to communicate in their language. You could try out being an informal tutor and if you find it has potential, you could further develop your career getting an online credential, for example an ESL credential, that would allow you to be a professional teacher and offer more of a variety of classes without having to get an actual university degree.

Muchas gracias por tu comentario, sin duda me has dado una mejor perspectiva de la situación.

Especialmente lo de venezuela.