If you have budget for it, I would run irrigation lines now. But don't use the cheap 1/2" black poly lines, run all of your irrigation in 1/2" PVC and then stub up to irrigation fittings inside of plastic irrigation boxes. The cheap black poly stuff never lasts more than a few seasons before developing leaks and costing you lots of money in wasted water. If you run the main feeder lines using sch40 PVC, they will last forever. And then, if you're there long term, you can install irrigation controllers with flow meters and know exactly how much water your surroundings are using. Also, make sure any irrigation or low voltage lines are buried in easily accessible runs; don't bury lines under hardscape. Things will always go wrong, leak or need repair and if you bury those lines under concrete you'll cause yourself an expensive headache later on.
As for plants....do yourself a favor and go with only desert/drought compatible plants. Too many people make the mistake here of trying to grow stuff that is not fit for the desert and then end up with either lots of dead/dessicated plants or they waste huge sums of money trying to keep everything watered. If you install a well designed drip irrigation system and use native plants in pots around the pool area, you'll have a very nice outdoor oasis that is low-cost and easily maintained. Chop down and remove any mesquite or palo verde tree that is within 100 yards of the pool! They are a mess and not worth having around.
