I have a collapsible (on request, not by accident) hydraulic lift hoist. Similar to:
http://www.princessauto.com/pal/en/R...rane/8210072.p
The issue I keep finding is there is not enough vertical rise when loaded. Put a weight on it, and the caster wheels take all the pressure. Try to move it around, and the load swings, or the legs foul against something.
If you are taking out an engine, consider how close you can get the body of the hoist to the engine compartment, then see if the hoist will have as much range as you need to hook on, lift it, and get it past the rest of the vehicle.