Vault will work with Inventor, AutoCAD as well as Office. When you install Vault, it will install a plugin for all these programs through which you can access and check in/check out files from the Vault.
When you need it for collaboration between multiple offices, then you'll need Vault Collaboration, as it can be set up with replicating servers (so that each office has up to date local copies, improving the speed). For this you'll need to buy networked licenses.