Steen,

it simply depends, how multiple languages have been implemented for your site:

• a landing page with different portals for each language - this allows greatest flexibility andindividual content per portal, but requires more effort for setup and maintainance
• a single portal with multilingual modules - this requires special modules, but the portal has in all languages the same pages and modules and is easier to setup and maintain

It depends, what had been the needs, you declared when developing the concept for your portal. For the first version, 8h for an additional portal are IMO justified, in the second case adding another language should be possible with less effort - but be aware, that you will need to provide every content simultaneously in every language - with 6 languages, this can become a nightmare!