Its not the parts, although a leaf-spring rig would obviously be cheaper (less parts). The real killer is labor. There is a TON of cutting, chopping, fabrication, welding, grinding, etc. All of that takes time. Shops around here (and I feel the midwest is cheap) charge anywhere from $40 to $70 per hour. You're looking at two-weeks (80 hours) if you totally know what you're doing, and you've done an H3 before. The problem is....very few people have. This "indecision" time is what kills the budget. I promise you...anybody that does an SAS on an H3 will spend way more time than they originally planned for. This is because there is no such thing as a "kit". You will have about a 40% success rate on pretty much every little task. Order. Wait. Receive. Test fit. Send back. Order again. Wait. Test fit. Okay...I can make this work. On to the next problem. And on and on it goes....seemingly forever. The worst part is: Our vehicles have a certain "high-end" reputation. This makes it even harder to take a torch to them.
Myself and a few others have been there. I'll help anybody that wants to give it a go. Its very fab-intensive and custom, even with advice. The first cut is the hardest.