$50 is a small investment if you think about how much time it would take to get back to HTML circa 2015. I downloaded but haven't started the trial version of Pinegrow, so I can't speak from experience how easy it is to actually use it. But their videos show that the web editor lets you manipulate themes before you even buy them, giving you a good idea if it'll work for what you want even before purchasing. (I did try that feature out and it works well!) It'll give you the ability to modify the theme as you validate your business until you get to the level of success that a custom design by a designer may make sense.
EDIT: Link to Pinegrow