Ask HN: What is a practical example of Machine Learning for a small business?

In general, small business has the problem of not having enough data set to use machine learning. However, I heard about a small guesthouse's example. They tried to use machine learning for dynamic pricing because they need to set prices properly depends on their supply and demand. I'm not sure the results of that. But It's an interesting use case using machine learning even if they are a small business.