The main goal of this Master Thesis was to show the possible methods of business evaluation and to verify the use in practice. For the detailed research, the Discounted Cashflow-methods were selected as main investigation methods. The problem is, that these methods can only be verified under restrictive assumption. For that reason, this Master Thesis shows the possible assumptions of the DCF-Evaluation formulas, to get uniform valuation results in practice. Doing the calculation of the enterprise value with the DCF-Methods, it might cause a circulation problem. This Problem can be solved with the Roll-back method und will be showed in this thesis by an example. Another central investigation area is the consideration of change in enterprise value, when the debt ratio is considered in calculation. So on the one hand the research questions consider the debt ratio in business evaluation and on the other hand, the possible assumptions of the DCF-Formulas. The research questions were answered theoretically by doing a literature research and additionally with two examples. The first example shows the change of the enterprise value when the debt ratio changes in height. The second example “Example business evaluation”, shows the different possibilities of business evaluation with the DCF-methods. That means, once the calculation with and without a constant debt ratio as well as the most important part of this master theses, the consideration of the change in enterprise value by using risky debt.