I am currently searching for a master and then a PhD in Finance/Quantitative Finance. Since I have a certificate in German Language, I could choose German-speaking countries (Switzerland, Germany, and Austria) since they offertheir master programms have low-fees masters fees and PhD students get paied in sciencecontrast with other countries as UK,etc.
My question is about pursuing a PhD and whether I could enhance my income by providing teaching assistance in the University. In these countries, are classes based explicitly on German or English? Moreover, do these countries offer a salary for a PhD student, or is the cost of living prohibitive?