Please don't buy the super cheap trolley jack. I was using one at a mates place and a front wheel gave way, the jack fell onto its side, and the car of course fell onto the floor.
2 lessons....always use chasis stands, and don't buy a jack form supercheap.
Many jacks will not fit under a Z so check first.....keep in mind you should never jack a car from the sills, you should use the front or rear subframe or possibly the chasis rails if you must. The jack will need to be loooow and long.