As the U.S. and Israel’s war with Iran squeezes global oil supplies, travelers have valid reasons to worry about the cost and availability of flights as they plan their late spring and summer trips. Experts say booking earlier, and staying flexible on dates, destinations and departure airports can help reduce costs. Packing light means avoiding rising baggage fees. Using airline points or signing up for a travel credit card are other ways to make flights more affordable. Travel experts caution consumers against purchasing Basic Economy tickets, though. Even though they are the cheapest, they may rule out refunds or credits if passengers need to cancel.