After reading the concerns about the space a lift would take up, I remember seeing these portable lifts:
http://www.northerntool.com/shop/tools/product_200386167_200386167
Maybe not this one exactly, but a similar model? Could be stored out of the way so that the space could be used for other things, no anchoring it to the floor to irritate the landlord, and if DMS moves, they could take it with them easily.