It depends on the size of the rig you are planning to buy.
For the money I think the stackable washer and drier that Mobile Suites puts in their rigs is the way to go. They are small dimensioned and fit in a single closet / cabinet. They hold a full size load. Not a "super sized" load but a full sized load and the drier is rather efficient for 110 volts. It has saved up over $60.00 a month in laundromat costs and up to over $80.00 at times. Forget about it while boondocking as it uses way too much water and electricity.
The dishwashers are a joke, they are too small for full size dishes. Really when it comes down to it we use disposable dishes to cut down on dishwashing. We still use regular silverwear but not dishes. The space the dishwasher would take up is far better used as cabinet storage.
If you are getting a smaller unit, forgo the appliances and use the space for storage as you'll need it.
Mike Nancy and the fuzzies
Fulltiming since June 2004
Volvo 660 MH tow vehicle
2005 MS 38RL
2007 Saturn Ion "toad"
2010 Gold Wing "piggyback"