A common use case to build an essentialist MVP is to get more support for your idea. Taking the functional demo and pitching it to an investor, so you get more funds to flesh it out further, and recruit more team members to mentor, give resources, ideas, and connections to the project. Here I'm going to discuss some considerations around building an MVP for this purpose.
First and foremost, show your prospect something new. Something they've never seen before. Even if the userbase has a population in the dozens and not millions, especially so. You get to solve a hyper specific problem, and it will be clear when you succeed at alleviating a pain. There is no need to build the ability for two members to DM each other. That functionality has been built, probably one hundred thousand times before. The investor doesn't care. Show him the innovation, is your special sauce tiny events, an asymmetrical marketplace, a new business case for ML. Only show one page. His time is scarce, and your resources to build are scarce. Keep it brief.
Use mock data to show off what could be. Make it clear you haven't signed pepsi to your brand, but show what could be when the vision is attained. Not just big brands, but diversity in users, and showing that there is a depth in what can be discovered in your product. Show the value that users will find given the valuable user content that is brought to you. You can mock some of this out, to elucidate the vision, and walk the investor down the path you want to show. Here's what we'll accomplish with some added support and funds.
You can stretch some of the capabilities when you have a small amount of data by using simple expert systems. For something like a filter or decision making by the backend, you can show some of the aspirational abilities of the software in real time with straightforward algorithms. They will be expanded upon and built out more robustly when funding is secured in order to be applicable to broader data sets and more users. But for now, you can show true functionality that looks impressive because you have limited data.
Overall, building a tech demo for an investor is one of the best ways to get support. Showing something tangible that can be touched and felt is powerful. Reach out if you want to boost your pitch to your next investor with an MVP.