Money need to be in the bank, potentially weird from abroad ,(retirement) before to apply to move to 90d non-o visa. And you need to have 15-20 (depends where) days left on your current legal stay when you apply.
now the question was for initial visa it seems to me: so for non-O 90 days visa for retirement you need to prove that money came from my abroad. For the extensions you do not need to prove that.