Before or after depend essentialy on what's more important (more important has to appear first).

So sometime it may be usefull to find another words to express a thinking, if this help to permit to locate most important words at first begin of a phrase.

While people who like to see project be born would say:

 -  Un projet certe onéreux

Trying to place the `bad` work later as possible.

People who find the project to expensive would say

 -  Un coûteux projet

Changing `onéreux` for `coûteux` as `Un onéreux projet` sound not well.