Hi D L;
Salvaging is much easier than relocating. You will be faced with your own particular costs and safety issues. The more you take them down in the opposite sequence they went up the more salvage you will get, such as stripping the roofing will allow you to salvage more of the boards without breaking them.
I have seen scavengers take down barns with not much more than a chain saw and pry bar, but to work carefully and safely I think you need a man-lift for only a day with careful planning or maybe a week which allows for some bad weather and more than just using it for the framing. A skid-steer is handy for loading out timbers, again careful planning can minimize rental time such as having piles of timbers you can drive to ready to go, you do not necessarily need to have a machine sitting around while pulling nails. You may want to find a machine with demolition tires to avoid flat tires.
Clean-up is another consideration. If you need to pile and burn the debris or load it out for disposal, nothing beats an excavator, although a bulldozer can make and move piles, too. Our local Kubota dealer has a mini excavator you can also put forks on so it could carry and load timbers and do cleanup work after putting the bucket back on (a thumb helps a lot). Again, planning minimizes machine time such as by making piles of debris as the material is generated where they can be burned so they do not need to be moved. This depends on the proximity to other buildings, etc.
You should be able to know what the longest timbers will be. We have moved 40' timbers on a pickup truck but generally if you have timbers that long you should count on using a tractor-trailer. Efficiently stacking the materials on trailers in a way they cannot shift and come off is very important.
Just as a reference there was a discussion about dis-assembly techniques in a previous thread:
http://forums.tfguild.net/ubbthreads.php?ubb=showflat&Number=13871&page=1Safety is the biggest problem. If you have more specific questions post them, but I only check the forum randomly these days.
Hope this helps;
Jim
