Unless it is rusted on, most come off fairly easily if you loosen the nut until the top of the nut is flush with the top of the shaft, pull up on both sides of the wheel while giving the top of the shaft / nut a sharp rap or two with a hammer. The wheel should pop loose. Easier with two people. Wheel pullers are not usually required. If you are careful to ensure the nut is not lower than the center shaft, you can't hurt the threads so no downside to trying this.
