The article deals with the problems that are solved in the development of methods for testing (verification) of measuring devices that are verified at several points in the measurement range. The verification method must provide the required reliability of verification results. The following criteria are used for the reliability of verification results: the risks of the customer and the manufacturer; the probability of a control error of type 2. These criteria are widely used in the development of methods for multi -parameter control of complex products. It is proposed to use the Monte Carlo method when developing methods of instrument verification. A simulation model of the verification procedure is developed for the case when the error of the measuring device (MD) is considered as a stationary random function. The reliability of the control results was evaluated taking into account the uncertainty of the measurements performed and the number of controlled points in the measurement range. The influence of the model of the MD error on the verification reliability indicators was studied. The results of calculating the reliability indicators when checking MD at several points in the measurement range for two models of the MD error are presented. The first model assumed the independence of the MD error values at neighboring verifiable points. The second model assumed a well-known correlation of the error at the neighboring verifiable point. It is shown that even with a high measurement accuracy, the choice of the model of the MD error and the number of controlled points significantly affect the customer's and the manufacturer's risks. When developing verification methods, it is proposed to take some abstract model of error in the form of a stationary random function as a basis. In this case, the use of a simulation model allows you to compare several variants of the method and choose the most effective verification method.