You can legally purchase rare money in a flee market. You can take a risk and purchase rare money on eBay as well, just watch out for counterfeiters!
-Supervisor edit-
cash money heroes
You can't buy them with money, but you can buy them with Battle Points at the Battle Frontier.
use your money to buy them from the shop.
You have to buy them with real money, so yes.
Just buy everything you can afford and be a rare and famous penguin.
You can't buy Rare Candy.
zero
If you want tonnes of rare candies, I suggest you save up your money to buy gameshark or action replay ds/gameboy advance to hack the game and get extra rare candies.
You can't buy rare candies!
Catch a Lv.50 and get alot of money, finally buy 10 rare candies 5x.
You can't buy rare candies in any game you can only find them
You can't buy Rare Candies in White.