Cheers Pete and nice one Andy.
Which card set is best to get?
The best card set is the basic fortune set which often comes packaged with the basic rulebook as a deal. That's plenty of cards to play the game. The only other thing you might need is a reward deck. ( the basic reward deck only has 5 cards)
But all the basic fortune and reward cards are printed in the base rulebook for you to copy and print them off yourself, if you don't mind home made cards.
(Edit, just checked and the Fortune deck ( 54 cards ) has all the basic fortune cards and the 5 basic reward cards as printed in the rulebook. Plus some spare blanks)