Short answer: sometimes, but don't count on it. Most urban outdoor furniture sets I've seen—think balcony bistro sets, modular patio sofas, small dining tables, and lounge chairs—include a basic tool kit. Usually that means an Allen wrench or hex key, the bolts, washers, caps, and a printed or digital instruction sheet. Some better kits throw in a small open-end wrench or a cheap multi-tool. But that's about it. You rarely get a screwdriver, rubber mallet, socket set, or drill, even when the assembly would go much faster with them.
The tricky part is that "included tools" doesn't always mean "enough tools." I've had sets where the Allen key was fine for 90% of the job, but the last step needed a Phillips screwdriver or a wrench to tighten a leg. I've also seen glass-top tables and fire pit tables that need two people just to lift the top, plus a soft surface to avoid scratches. If your set has to be anchored to a wall, deck, or concrete patio, you'll probably need a drill and masonry bits—those are almost never included.
So how do you know before buying? Check the product page under "What's in the box" or "Assembly." Look at the manual PDF if it's available. Customer reviews often mention whether the tools were usable or missing. If the listing says "assembly required" but doesn't list tools, assume you'll need your own basic kit. A good starter kit: Allen keys, Phillips and flathead screwdrivers, adjustable wrench, rubber mallet, tape measure, and a power drill with bits. A second person helps for big sofas, tables, and anything with glass or stone.
Do you need to hire someone? Not necessarily. If it's a simple two-chair bistro set or a small side table, most people can do it in 30 to 60 minutes. If it's a large modular sectional, a dining set with a heavy table, or anything that needs anchoring, hiring a handyman or assembly service can be worth it. Retailers sometimes offer assembly at checkout, and apps like TaskRabbit or local furniture assemblers can handle it. Expect to pay depending on your city and the size of the set.
My rule: if the box is heavy, the instructions are longer than 10 pages, or you don't own a drill, get help. Otherwise, open the box, sort the hardware, pour a coffee, and give it a try. Just don't tighten every bolt all the way until the whole frame is aligned.