Accurate and realistic estimation is always considered to be a great challenge in software industry. Software Cost Estimation (SCE) is the standard application used to manage software projects. Determining the amount of estimation in the initial stages of the project depends on planning other activities of the project. In fact, the estimation is confronted with a number of uncertainties and barriers’, yet assessing the previous projects is essential to solve this problem. Several models have been developed for the analysis of software projects. But the classical reference method is the model, there are other methods which are also applied such as Function Point (FP), Line Of Code (LOC); meanwhile, the expert`s opinions matter in this regard.