You are picturing the table, the food, and the people you love gathered together in your living room. Hosting at home keeps venue costs at zero, which leaves your budget for the things people actually remember. The trick to keeping it small-scale and stress-free is knowing what needs your attention now and what can wait until next week.
Bridal showers live on a hard calendar. Because you have a fixed date, you need to work backward from it so you aren't rushing and overpaying for flowers or catering. A solid timeline lets you pace out your costs without feeling the pinch all at once.
That 0% window is a deadline, not free money. If you still have a balance left when the 18 months are up, interest kicks in on what is left over.