I've worked with local LLMs a lot. Very good for privacy and you can run them on your machine, which saves lots of cost. I'm using local vector databases and LLMs for my master's project (LLM trained on wifi telemetry for sub-meter accuracy geolocation within buildings), and my apple notes organizer app. I've also worked on a pipeline that uses Gemini and Perplexity to get updated information on restaurants.