Step one is to try to figure out what your end goal is for this lift kit. If your goal is to just make the car taller so it looks cool, or to fit bigger tires, but you're not that concerned with off-road performance, then a simple spacer or perch collar lift would most likely fit the bill. These can cost as little as a few hundred dollars. But note that if you do go 3" you should get aftermarket front Upper Control Arms as well, which can easily double or triple the cost of the lift kit. The UCA's are necessary because they help correct steering geometry (Caster, mostly), which is impacted when lifting the vehicle but not changing the pivot points of the suspension links. At 3" of lift, you'll be just into the range of needing aftermarket UCA's. At up to 2" you can get away without them. At 3", the alignment shop might not have enough range of adjustment to dial your alignment back in to factory spec after the lift.
If your goal is better handling on-road and especially off-road, suspension systems that replace the entire coilover shock/spring are necessary. There are a ton of options on the market, ranging from expensive to very expensive, so for folks who "just want to fit bigger tires" this might be overkill. I won't list all of the options available out there but I will mention my company's products,
ICON Vehicle Dynamics. We offer 8 stages of suspension systems for Bronco. At the lower end we do offer spacer kits, and ours is for the lift height you mentioned. I ran that kit on my 2-door for a while and it worked fine for providing the room to run larger tires. We also offer a product called the EXP Shock, which is a high quality shock with built-in lift height and improved handling, but keeps the stock coil springs. These are sort of an intermediate product that fits into that wide price gap between spacer lifts and full coilover systems. But the bulk of our product offerings are our complete coilover systems. Those also range wide in price as you go up in features and performance. Our top of the line system includes fully electronic, reactive, on-the-fly shock tuning that instantly adapts to whatever terrain and speed you're driving.
By the way, other vendors are welcome to recommend their own products here, if they'd like. I both run this forum and work for ICON, but we always keep this So Cal Broncos forum and our social media groups open and welcome to all vendors and manufacturers. But its up to them to tell you about their stuff, not me LOL.
Best of luck and feel free to ask any questions.
