I’d start with the least aggressive method and only step it up if needed. First, identify the finish—powder-coated metal, painted wood, plastic, or concrete—and test anything you use on a hidden spot. A plastic scraper, warm soapy water, and a soft cloth will often lift fresh stickers or light marker without harming the surface. Avoid metal scrapers, wire brushes, steel wool, acetone, lacquer thinner, and aggressive pads, because they can scratch or dull the finish fast.
For stickers, soften the adhesive first. A hair dryer on low heat is usually safer than a heat gun; keep it moving and don’t hold it close enough to blister paint. Peel slowly from a corner with your fingers or a plastic scraper. If residue remains, try a citrus-based adhesive remover or a little isopropyl alcohol on a cloth, again after testing. Goo Gone–type products can work well on metal and plastic, but wipe them off thoroughly and don’t let them sit on wood or porous concrete. For stubborn residue on powder-coated metal, a small amount of WD-40 can help, but clean it off afterward with soapy water so it doesn’t attract dirt.
For graffiti, figure out whether it’s acrylic spray paint, marker, or something oil-based. Start with warm soapy water and a soft cloth. If that doesn’t touch it, try a graffiti remover labeled safe for your finish. Apply a small amount to the cloth rather than pouring it on, let it dwell briefly, and wipe gently. Don’t scrub hard; you’re trying to dissolve the paint, not sand the finish. On powder-coated furniture, avoid harsh solvents and abrasive “magic eraser” pads, which can leave a dull patch. On wood, use the driest method possible and avoid soaking the surface; after cleaning, reseal or oil the spot if the finish looks tired. Concrete can take a little more pressure, but don’t blast it with a high-pressure washer, especially if it’s sealed.
Work outside or in a ventilated area, wear gloves, and follow product labels. Rinse with clean water and dry the furniture fully afterward. Once it’s clean, a coat of car wax on metal or a fresh sealer on wood and concrete can make future sticker and graffiti removal much easier. If the graffiti is on public property or a shared street fixture, it’s often best to report it to the city or property manager rather than use stronger chemicals yourself.