Autodesk has recently created a webpage whereby you can download your Revit content in .exe format for Revit 2016 and 2017. No 2018 at this point or add additional content if you did not install your Revit software correctly or for some reason your content is missing.
The time saver here is that, in the past you had to uninstall Revit and reinstall to re download the correct libraries. This could have been a timely process and with this new download page it saves a lot of installation time.
For multiple installations, you can also do the following. You can visit the site below and download the appropriate content libraries and then use this to install at the multiple Revit installations.
How would you install the multiple Revits? You could download the normal Revit install files from your Autodesk Account or from the Virtual agent
Then using these files install Revit making sure you select the appropriate content libraries but then also make sure your internet connection is switched off. Reason is that if you have your internet on Revit will start download the selected content in the background. You don’t want this as you have used the Autodesk site below to download the content already.
Autodesk Revit 2016 and 2017 content download site: https://knowledge.autodesk.com/support/revit-products/learn-explore/caas/sfdcarticles/sfdcarticles/Revit-Templates-and-families-not-installed.html
Once downloaded you can install the content. running the exe file it extracts to the correct content folder for Revit libraries eg: C:\ProgramData\Autodesk\RVT 2017. See below.
One thing you also just need to check is the library path setup inside Revit’s options to check that the path is set up that points to your newly installed content.