The article compares the Black-Scholes and Leland models for pricing options in real markets with and without transaction costs. The two models show different performances when transaction costs are involved. By analyzing stock prices over ten days, it was found that changes in conditions can impact option pricing. The introduction of transaction costs leads to deviations from the models' theoretical prices, with higher costs resulting in larger discrepancies. This study highlights how transaction costs can affect option pricing in real-world scenarios.