From what it seems, Pacaso isn't claiming to actually buy or sell property on behalf of anyone, they're setting up an LLC for fractional real estate investment, and:

> choosing and managing the property management company; maintaining the LLC and resolving any disputes between owners or the municipality; continually innovating and improving the Pacaso app

But it does seem like it's a gray area. Obviously I'll need to consult an attorney but I wanted to get a better idea of the situation first.