Under the description of the navigator career path (around page 62 of the core book or close by it), it is stated that navigator and weapon proficiency (universal) are starting talents for that particular career path.

Now if you look a bit further down the page it states that at rank 1 those very same talents costs 100 xp to gain. This seems a contradiction in terms that you get 2 talents for free and at the same time can buy them at rank 1.

Am I missing something? Does the starting talents only give you a choice of 1 talent to choose from? Or is it simply a missprint?

The rules state that they're there for redundancy - in case you need to know the XP costs for those starting talents/skills.

You don't/can't buy them again.

From the Rogue Trader Living Errata , page 2, sidebar "Duplicated Skills and Talents"

It is important to note that many Career Paths starting
Skills and Talents are duplicated at Rank 1 of the
Career’s Advances. This is an intentional duplication,
and represents the training that is available to all
Careers regardless of their origins. Future expansions
for the Rogue Trader line may feature Alternate Career
ranks or backgrounds with different starting skills,
and therefore, this duplication serves a purpose for
the overall Rogue Trader line. If a character already
possesses such a Skill or Talent from Character
Generation, they may not purchase it again at Rank 1.

Thanks for that. No longer does confussion rule my mind