i am just going to toss you into "confusion" err the deep end....
there are a few companies out there that make, rear blade, box blade, snow blower, even buckets, and like for "fork lift machines" most of the stuff slides right on over the forks like a pallet and away you go on the fork lift. other words multi companies out there need forklifts for common day to day stuff. and instead of getting a new tractor or something, it more likely easier for them to get a couple implements for the forklifts that they already have.
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some initial things i think about.... is a forklift is able to turn on a dime and get into nice small locations for both loading and unloading. vs a tractor or larger machine.
with above in mind a "skid steer" larger unit might work for you. but you are looking at the larger skid steers out there... for example...
Bobcat Skid-Steer Loaders - Bobcat Company (down at bottom of page there is a film strip showing max lift for various units use the arrow to scroll to the right)
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www.power-trac.com different type of machine all together. were everything connects to the front. and kinda a cross between regular tractor and skid steer. (wouldn't mine owning one of these)
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www.tractorhouse.com = agirculture tractors
www.machinerytrader.com = industrial equipment (sister site of tractor house)
SearchTempest: Search all of Craigslist nationwide & more = search multi cities of craiglist .org at one time.
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about only thing left out from what others have noted.... is buying a deck over trailer, and making sure leaf springs set on top of the axle. ((in attempt to give more ground clearance)) so you could pull a trailer up and down the area. you might need a couple trailers. one to haul the fork lift, other to move goods