Any Dropbox experts here?

I have a Pro account with shared access to a number of people, some as admin and some with read only. I want to protect certain folders that contain confidential information. I would like them set up so that a password is required every time to open them. This would address concerns around people having the app on unsecured devices that they could leave lying around or lose. Sounds quite straightforward, password to access a folder, every time.

I am struggling though, anyone know how to do this or can suggest suitable alternatives?

Ta

Dropbox for Business might support that, but not the basic Pro account.

You could just encrypt the folders by zipping them using a password to unzip – or encrypting the underlying Office docs using the Office encryption option?

Business will be too expensive. Will try the zip method at folder level, too arduous doing it for each document but folder might work