It is the most important to design a high reliability system by adopting suitable maintenance policies. Various maintenance models have been formed stochastically and their optimal policies have been derived analytically. In such studies, when the maintenance costs are the same, it has been discussed theoretically which policies are better. This paper proposes the problem of determining maintenance costs when the expected costs of two policies are the same, which is called a balancing cost. We take up the age replacement and the periodic replacement with minimal repair and obtain their balancing costs numerically. Furthermore, we make this approach to replacement overtime policies and a shock and damage model.