Ask HN: What Small Businesses/Industries Do You Want to Know More About

I want to launch a podcast next year, where I talk to small/medium sized business owners about how their business operates, the problems they face, and what makes their jobs hard. My goal is to expose the "What Should I Build?" crowd to multiple industries / business problems. (and to show that getting out there and asking questions is valuable, not scary!)

Are there any small businesses or industries you wish you knew more about? What do you wish you knew?

Thanks in advance!