User

user.cs

public class User
{
    public string FirstName { get; set; }
    public string LastName { get; set; }

    public LoginInformation LoginInformation { get; set; }

    public class Comparer : IEqualityComparer<User>
    {
        public bool Equals(User x, User y)
        {
            return x.LoginInformation.LoginLocation == y.LoginInformation.LoginLocation;
        }

        public int GetHashCode(User obj)
        {
            return obj.LoginInformation.LoginLocation.GetHashCode();
        }
    }
}

public class LoginInformation
{
    public string LoginLocation { get; set; }
}