Advice on Planning a Cableway on a forested hillside

Hey all, I've been working on my mountainous NorCal homestead for about 8 months now and after packing all my yurt supplies and furniture on my back up a 30% grade I realize that its time I built a pulley to more easily get heavy stuff from the road to the home-site. I need something that can pull up to 500lb uphill, through trees to the ridge, the cableway also has to bend in a couple places which seems technically possible, but the only information relevant to my needs are about commercial cable logging, or backyard ziplines, not a lot in between. My question is: does anyone have experience doing something like this or know of any material I can read to become more acquainted with home/farm-scale cableways? I need to start surveying a path, and I have a rough idea where I want the line to go, but would greatly benefit from surveying advice. This seems like the closest thing to what I'm after, but still to heavy duty industrial than what is necessary: https://youtu.be/0-G46lkIU9Y

TO:  Cama Zotz
FROM:  Eric Koperek = erickoperek@gmail.com
SUBJECT:  Cableways
DATE:  PM 5:23 Thursday 8 September 2016
TEXT:

(1)  I come from Austria where my family has used cables for mechanical power and transport since the Renaissance.  Our cableways are powered by water.  Your system will most likely be powered by electric or diesel engine.

(2)  A good place for you to start reading is:  www.lowtechmagazine.com

(3)  You might also search the Internet for "Ski Tow Lines" and similar headings.  There are companies in the United States that can provide necessary equipment.  This is the cheapest option for your situation.

(4)  You should also consider construction of a "step road" like found in the Andes mountains of Peru or Italian hilltop villages.  If this is your residence, you should have "back-up" access in case your cableway fails for any reason (most likely engine problems).

ERIC KOPEREK = erickoperek@gmail.com\

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