Does employee have to pay back the rent or courses that they take to the employer?

I had an offer from a company in Rostock. They wrote in their contract that, they will pay for relocation and rent for the first three months. And if the contract ends somehow before a year, I have to pay the rent back, I think it was some ratio rule, so, each month I stay the total paid costs to pay back reduces, and if I stay for a year, I don't have to pay anything back. So, it's really strict rules to bind the employee. Same goes for the courses I take. They explicitly wrote:

"If the additional courses or training is discontinued for reasons for which the employee is in-charge for, the Employee is obliged to repay the full costs back to the company".

Is it common here in Germany to have such clauses?