I conduct research in the field of corporate finance, focusing mainly on the mathematical methods of present value calculation and the estimation possibilities of the cost of capital. The "textbook" way of present value calculation relies on several simplifying assumptions; therefore, it merits examination, when relaxing these assumptions, what mathematical formulas are applicable and what distortion they carry. Estimation of the cost of capital (discount rate) is especially difficult in cases when there are no stock price data available directly about the asset subject to valuation. Other kinds of data (e.g., cash flow data), however, might be available; therefore, it merits examination how, by what method, the cost of capital could be estimated particularly for the asset subject to valuation. All these examinations could aid in establishing the value of an asset more precisely.