Portable are on wheels with finished tops and sides. If you have limited space in your kitchen or if you rent a portable may be your best bet. Most models can be converted into under-counter mounting . However, because of the additional connection hardware and finished sides, portables usually cost more than similar built-in models. U.S. versus European Many US stores carry US and European dishwashers.
European models are generally more expensive, quieter and more efficient but less effective.
Size Most are 24 inches wide. Some are 18 inches wide. Interior layout configuration of sliding racks, baskets, trays. Does the washing arm reduce the amount of loadable space. Many budget units now offer this feature.