My monthly credit card bill is usually under US$50, but if I'm
travelling or on vacation, it can spike upwards to nearly
US$500.
I don't like using credit cards and prefer to pay for my purchases
with cash or a check, but you might not have a choice for some
transactions (for example, paying for merchandise purchased from a
mail order vendor). I do, however, make it a point to pay off all
my credit card debts when they become due, and consequently have
never had to pay any interest on them.