Save Money, Conserve Water, and choose plants that do great naturally in this area
There are plenty of plants you most likely already know, that are california native. Lavender, rosemary, catmint, heuchera, coreopsis. penstemon, various sages, ceanothus (Wild Lilac), Flax, salvias, oreganos, thymes, santolinas, yarrows, verbenas, and many more, not including the many various ornamental grasses. Ask your landscaper or check your nursery to select and combine plants and planting areas that have the same soil and water requirements. Using Large boulders and variations in foilage can help with water conservation and make for an interesting design.