Is it possible to run multiple versions of SVN on a single machine?

With the Collabnet Subversion binaries, this is not possible due to the nature of the installer.

Even when building from source, both Subversion's and Apache's binary and library interface are subject to change from version to version. It is very easy to make a change in the staging environment and have that change unexpectedly propagate over to production, due to the dynamic linking system.

The suggested method is to stage on a separate staging (virtual) machine. This removes all possibility of corrupting an existing production instance while testing a new version.