collective.behavior.price provides price related behavior to dexterity content types.
The behavior can be added through the web or directly through the file system to the dexterity content type xml file like:
<property name="behaviors"> ... <element value="collective.behavior.price.interfaces.IPrice" /> ... </property>
You may also set currency through content registry and content price with currency will be also cataloged with metadata called money.
You may list collective.behavior.price to buildout.cfg or setup.py in your own package.
Use zc.buildout and the plone.recipe.zope2instance recipe by adding collective.behavior.price to the list of egg:
[buildout] ... eggs = ... collective.behavior.price
You may also list to install_requires to setup.py within your package.