Sharing content between different sites

Hi there. Sorry if this topic was already covered. I did search around, but the only information I could find relating to this topic was outdated by two years.

I would like to share some content between different sites. For example, I am setting up a news and information publication for my community using WordPress. I am also setting up a standalone rental guide site and a standalone nightlife guide site. When I say standalone, I mean they will be there own sites with a different design. I could use Multisite, if that is the direction suggested.

So, on my news and information site, I would like to allow some content from the rental guide to appear in a widget, the same goes for nightlife events. For example, when visiting my news website, I would like readers to see the five most recent rental listing and what events are going on that day.

Is this possible? Should I be using Multisite to achieve this? Any links to recommended reading would be great. Thanks a bunch!