Late summer in New Orleans brings lower hotel rates and a slower pace to the French Quarter, making it the ideal time to soak in the jazz clubs and historic ironwork balconies without the crushing crowds. You get the same world-class brass music and Creole architecture for a fraction of the spring festival prices, provided you can handle the afternoon heat.
A typical trip runs about $1600 for flights, a solid place to stay, and eating your weight in po'boys and gumbo. Spreading that cost out over time makes it manageable instead of a massive hit to your checking account all at once.
That 0% window is a deadline, not free money, and any leftover balance when the 18 months end will get hit with standard interest charges.