Comments of chapter undefined of Starting Today I'll Work As A City Lord

wait what? can a baron even issue his own currency system? would the monarch of the country even allow such a thing? the country where his noble title is tied to should have their own currency and it makes no sense for MC to create his own currency system cause he has no power to do so right? his currency system will hold no value, meaning it would be useless to use it outside his city. I don't understand this anymore