I know of someone who joined as a Contract Capt, he has not much more than 500 Command time. Money is good, a 6 mth contract with very high possibility of extension (probably on 50% ) into the Winter.
Bases proposed were Billund, somewhere else I don't remember, and Iceland. Roster/ money was (if I remember correctly ) sightly better in Iceland.
You are employed via their Latvian AOC, as far as I know tax/social is YOUR responsibility.