Preview/teaser content like Glassdoor

I’m looking to create a review website. But would like to display a portion of available reviews to unregistered users, but display a teaser/preview/call to action, that encourages users to register to gain full access.

Is there a plugin that can achieve a similar teaser layout, say the first 3 review for an item, and semi-hide or blur out the rest of the reviews, similar to Glassdoor?

Additionally, it would be nice, that once a user registers, based on a certain action, say add their own review, does it unlock access to more content/actions. What plugins exist for this?

Thanks