For a huge multifamily development project like The Avalyn in Chula Vista, Calif., there’s no shortage of challenges for builders to deal with. Many of these vary from unit to unit, since this eight-building, 480-unit, 528,000-square-foot complex contains everything from one-bedroom flats to three-story town homes. But no matter the layout, every unit is going to share one thing — a shower and/or tub enclosure, each of which takes a whole lot of time, precise finishing work and several assorted materials to finish.