Clean entire work directories

As a Bamboo user

I want Bamboo to ensure the entire build-job directory is empty in advance to running a job therein

so that builds do not fail due to leftover from previous builds

Notes:

• Job option "Clean working directory after each build" as a post step seems not be sufficient since it is obviously not be performed in certain cases, e.g. Bamboo / host shutdown and HBK.
• Source Code Checkout option "Force Clean Build" is not sufficient since in the case the checkout is done into a sub-directory "Checkout Directory" (required when build depends on several repositories), this option takes care only of the sub-directory(s).

I just see two possibilities to fix build issues due to leftovers of previous builds

• cleaning up entire work directory before / as the first task of every build
• configuring Bamboo to include the build number into the path of the current build directory (preferred)

Are there any option for one or the other?

PS: In our team, we recently discussed removing any created files by our own, however came to the conclusion that it is worse strategy with no guaranty that nothing else is being removed from build hosts unintentionally. If unique build directories are not possible, Bamboo tooling should be used to ensure clean directories beforehand of a build.