How to structure DB Collections

Okay, so here is the question: Is it better to use one or two collections? (here is the scenario)
Two types of users (members)
First, are companies. Companies signup and can sell their services.
Second, is people that signup to buy the services that the companies are selling.

Is it better to create two different collections for these different types of users or should it be one collection of users that are filtered by a TRUE-FALSE field for business or not a business?
What would be best?

Two collections IMO.

Future proofs and of course a big company will have more than one user.
Better by design, less empty fields in your table.

All users are members, only some users are company employees.

Yeah, that what I was thinking. Thank you for the insight.