I have demo-ed houses with a crawler loader, then a backhoe and skidsteer with a stump bucket with grapple. Now am using an excavator, by far the easiest and the fastest way to go. Most any method can be used, just the work and time is the biggest difference. If you do it slowly and a lot of hand work you can salvage useable materials. I did that with a pretty good sized building, the floor joist were almost all #1 fir and so were the 6 X 6 post and beams. A lot of the flooring is now wainscoating on my porch and trim around the windows. The rest I will probably sell, some of the big city people love old lumber and there is good money if you want to work at it. Insurance is a must, don't try to do it without. You can loose way to much. All areas are different about license, do it right and save the problems. Keep the area cleaned up and safe, people who want that kind of work done see those things.