Late September is the sweet spot for Iceland. The summer crowds have thinned out, the waterfalls are flowing hard, and the nights get dark enough to catch the northern lights without freezing your toes off.
A typical weeklong trip runs around $3,200 for flights, a rental car, and stays. Instead of dumping that cash all at once, you can spread the cost out. Using the Discover it® Cash Back card gives you a 0% intro APR for 15 months on purchases and balance transfers, which breaks down to about $213.33 a month to clear your balance interest-free.
Keep in mind that a 0% intro APR window is a deadline, not free money. If you still have a balance on the card after 15 months, standard interest rates kick in on whatever amount is left.