You could rig two double or triple blocks & tackle to lift heavy objects (see link below), can't beat this system for portability and utility. If you have a stationary frame to hook the top block from (like a steel beam or wood frame) you should be all set...otherwise you'd have to build a large tripod or other structure to support the blocks. Hope this helps.

http://goo.gl/rDHwJ

This is a solution used by wood turners to get logs in and out of their truck beds. It could easily used in a car trunk or suv back end. I have seen them but do not own one. It does require a trailer hitch. The trailer jacks and the crane are not too expensive, the welding ...YMMV As described it will store pretty easily. http://www.woodcentral.com/cgi-bin/readarticle.pl?dir=turning&file=articles_594.shtml

How often are you doing this? If it is a daily occurrence is s small pickup, SUV, or minivan a better vehicle for you? A vehicle with a full accessible hatch/flatbed storage would be easier to load and unload using ramps if needed, but you can't get around the lifting with a trunk.

"100-200lb objects" eh? Why not just, er, separate the major components and lift them out individually? That way you can dig smaller holes to dispose of them. 5 or 6 trips should see the job completed.

An engine hoist may be the easiest general-purpose solution (or equivalent — I have a medical lift that's the same design with a hand-operated hydraulic ram to raise a boom).

Simple machines and your brain are probably the first tools to consider. Can you put the objects onto a wheeled platform then use a ramp? Can you use a lever (or put something under the objects with extended arms to add leverage)?

A lift table. Here is a very inexpensive one from Harbor Freight:

http://www.harborfreight.com/500-lb-capacity-hydraulic-lift-table-94822.html

Habor Freight has a number of useful tools to solve this problem. The first thing that flies to mind is the 1-ton shop crane:

http://www.harborfreight.com/1-ton-capacity-foldable-shop-crane-93840.html

You might also consider the electric hoist with remote control, though it would require professional installation:

http://www.harborfreight.com/110-volt-440-lb-capacity-electric-hoist-with-remote-control-40765.html

If you don't need or want the electric option, they have a variety of manual chain hoists, e.g.:

http://www.harborfreight.com/1-ton-chain-hoist-996.html

This has really been bugging me...my instinct is to answer "a bunch of guys" but that's not reliable or realistic.

What I keep coming back to is a Gantry Crane. While a bunch of guys would be best for loading and unloading a car trunk, something simple & lightweight might be what you're looking for.

Here's something you might be able to model something suitable for your purposes.

Find This Best 1 ton Manual Chain Hoist

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