static void Main(string[] args) { service.CreateAccount( new Account { AccountType = AccountType.Base, Balance = 300, FirstName = "Vasya", LastName = "Pupkin" }); service.CreateAccount( new Account { AccountType = AccountType.Gold, Balance = 500, FirstName = "pasha", LastName = "vaskin" }); service.CreateAccount( new Account { AccountType = AccountType.Silver, Balance = 400, FirstName = "sasha", LastName = "pashkin" }); var account = service.GetAccounts(); foreach (var item in account) { Console.WriteLine(item); } Console.WriteLine("Add balance"); foreach (var item in account) { service.AddBalance(item.Id, 50); } foreach (var item in account) { Console.WriteLine(item); } Console.BackgroundColor = ConsoleColor.Red; Console.WriteLine("Remove balance"); foreach (var item in account) { service.RemoveBalance(item.Id, 50); } foreach (var item in account) { Console.WriteLine(item); } Console.ReadKey(); }