There is not a general answer to the question How much does a sworn/certified translation cost? As a reference, you can consider the JVEG (German Act on Payment and Compensation by Judiciary Authorities), but otherwise it's fairly common that both client and translator agree upon a individual price for a certain translation. As far as I'm concerned, I always offer a quotation (fixed price) in advance for every translation/interpreting service.
As a guideline, here is a list of approximate rates I may apply in order to set a price quotation:
And how much do interpreter services cost? The costs involved in interpreting must be calculated differently, since they often include hotel accommodation, meals, transportation costs and preparatory work. In addition, the interpreting services are commonly charged per full day or half-day.
Approximate fees for interpreting services according to their different modalities (simultaneous, consecutive and liaison interpreting):