I did this back in college. I had a Perl script that takes in a text file (before markdown) and generate a static one page site for local small businesses. I started with $250, depending on complexity. Ongoing maintenance was $25 a year for domain registration/server maintenance/etc, plus extra whatever they want to add. I was making a good profit, but getting customers was my issue. I cold called a lot of shops and even handed out my business cards to other shops.