Summer block parties live or die by the food, but waiting until May to book a truck is how you end up grilling cheap hot dogs yourself. The best trucks lock their warm-weather calendars by March. If you want good tacos or wood-fired pizza parked on your street, the work starts in late winter while everyone else is still shoveling snow.
A typical catering package for a full street runs about $2,500. Planning ahead gives you the lead-time to collect cash from neighbors, stagger your deposit, and spread the cost out so nobody takes a hit all at once.
Keep in mind that an intro window is a firm deadline, not free money. If you still owe money after the 15 months are up, standard interest applies to whatever balance remains, so set your auto-pay to at least $166.67 from day one.