Modern aviation is undergoing a transformation driven by innovative aircraft configurations, particularly More-Electric Aircraft, propelled by technological advancements and a pursuit of greater efficiency. This paradigm shift carries significant implications for maintenance costs. Early in the design process, it is essential to estimate future costs, including maintenance cost, to best decide which concepts are the most promising from a cost perspective. As the project progresses and design details become more defined, the impact of potential changes on costs might become substantial. Therefore, having cost estimates available in the early design phases helps mitigate the impact of configuration changes on overall expenses.