How do you suggest we finance lighthouses without arresting people and putting them in prison for the crime of walking down a road that happens to be in line of

How do you suggest we finance lighthouses without arresting people and putting them in prison for the crime of walking down a road that happens to be in line of sight of a lighthouse while not wearing a company-approved blindfold? As a libertarian I think we should seek a smaller role for government in people's lives. But I also think if something is in fact a function of government, we would be better off to admit it and formally finance it as such, than bring it in the back door by dishonest means.