A fire pit and some chairs turn a patch of grass into a second living room. You go from sitting on the couch to watching the stars in about a weekend. Late summer is the sweet spot for this project because retailers want to clear out patio gear to make room for snow blowers. You can usually grab the whole setup for about $900 if you shop the clearances.
Don't just buy the first kit you see at a big-box store. Get at least two quotes if you are hiring someone to pour a stone base, or check local listings for used pavers. If you use the right tool, we can break that $900 into $50 monthly payments and avoid interest while you enjoy the nights outside.
The 0% interest period is a strict deadline, not free money. If you still have a balance after those 18 months, the standard interest rate kicks in on whatever is left. Stick to the $50 monthly plan to make sure you finish the payments before the clock runs out.