The global max level cap for all players is 24 until they open up the new areas.
However you will need to unlock the areas past Shigemori River to increase the cap past the initial 1 to 4. Each new area you unlock will increase the cap.
As for being "not free". If you mean you *have* to pay RM to unlock the areas... the answer is no. The currency used in game is called Karma and its dropped by monsters so you can just theoretically just grind for the currency for the unlocks.