I think only retired players with at least a 10k salary get to be a free agent.
The minimal salary is different depending on age and nationality.
What are you basing that on?  I don't know the answer, but my experience is that there is one salary number (occasionally adjusted up by the BBs), independent of age or nationality.
Maybe I am wrong -- at one point I thought the goal was to preserve the best players, per nation, so that the FA number was adjusted depending on the maturity of the league. So I "catalogued" this concept in my head and haven't thought about it much since.
However, given that I haven't seen too many free agents recently it is likely that I am incorrect and you are right.
I'm 99% sure there's no nationality factor.
However, there was a slight modifier for very young players, although I don't know what that modifier is.
NO ONE at this table ordered a rum & Coke 
 Charles: Penn has some good people 
 A CT? Really? 
 Any two will do 
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