Is that best way to get there? Bus to cab?
Best way would be cab to cab! But bus to cab would be more cost efficient. If your considering going, keep in mind that you can not get a visa at the allenby bridge, you will need to go to the Jordanian consulate before hand to obtain one, only the border by Eilat gives visas at the border. (this is for USA citizens, i don't have experience with Israeli citizens).