Jepp, Command Tax gilt nur fuer die Command Zone.
PS: Und der Cast aus der Hand musst du auch nicht spaeter fuer die Command Tax mitzaehlen.
Commanders begin the game in the Command Zone. While a commander is in the command zone, it may be cast, subject to the normal timing restrictions for casting creatures. Its owner must pay for each time it was previously cast from the command zone; this is an additional cost.