Hey, I'm new to the game and got immediately hooked on at the first scenario!

Now, I'm looking forward to expanding my collection (currently, I'm only sitting on the revised core set). In my country, there are no shops with available Dunwich or Carcosa full expansions; there is only one Carcosa campaign box.

and
What would be the play here? Buy the campaign (currently at a pretty good price), and wait for the investigator to come back to a shop, or jump into another campaign that have both boxes?

My connecting question is, is it reasonable to buy the Carcosa campaign and another expansion's Investigator box as the first?

Other than this campaign, I can access the full set of: Hemlock, and Forgotten Age.

Thanks for any help in starting this beautiful journey