The supplier estimation and selection process is far from the TCO (Total Cost of Ownership) concept usage in many Russian companies. The majority of companies generally focus on the price, paying no attention to other significant for finances factors. In this article the correlation between the company’s procurement function maturity and the applied supplier estimation and selection methodology is provided. The widespread mistakes of typical methodologies usage are discussed. The recommendations for taking into account the maximum number of significant factors are given. Also, the ways for changing estimation models from one to another, more advanced, are mentioned. The conclusions about the different methods usage practicability on different companies’ evolution stages and the necessity of reconsidering and changing these methods with the companies’ increase and development in order to correspond with the global tendencies are made.