Costa Rica in May or September is ideal for catching the best weather before the rains hit their peak. You get quieter beaches, cheaper jungle lodges, and enough time to explore both the Caribbean and Pacific coasts without the usual crowds.
A trip like this usually runs about $3500. Using the Discover it® Cash Back card, you get 0% intro APR for 15 months on purchases and balance transfers. This lets you break that cost into manageable pieces.
Remember that the 0% intro APR is just a window, not a free pass. If you still have a balance after 15 months, the regular interest rate will kick in on whatever is left, which makes the trip much more expensive.