Why ain't the tornadoes washing the dishes? Too young? Otherwise, bring on the child labour!
Yes for the four year old, nope for the six year old. That said, they do help clean and clear the table and kitchen.
Just to be clear, we cook 95% of our meals. I have been cooking for 30 years, my wife for 10, and we understand fully the principle of clean as you go. That's why there is very little hand washing when the meal is done. We only have four bowls, four plates, and 8 of each piece of silverware. We have a handful of pots, pans, and baking trays. What do we wash? The plates and bowls from the meal, silverware, cookware, small appliances (blender, etc.), food storage containers (we make a lot of our food ahead of time), and drinking glasses. Enough to fill the dishwasher once a day, sometimes twice (if we cook a big meal).
That said, with the dishwasher, cleaning after meals for four has gone from an hour, or more, a meal, to 10 minutes at the end of every meal. That is the facts. That 2.5 - 3 hours we've gained back in our life is more than worth it. Also, I work as a merchant mariner. I am on a ship for four weeks, then home for four weeks. So, half the year, my wife is a single mother to two small kiddos. She is a busy person during that time. Saving her three hours a day, and a metric fuckton of stress, is utterly priceless.
And that $400/mo number is not a reality for us. Our entire electrical bill for the month is less than $100. Our water is free (well). I would say dishes maybe cost us $20/mo. For our family of four, in all sincerity, the dishwasher has been voted as the best purchase we have made in the last four years.
So, there you are. We have considered the cost and benefits of the DW, and the benefits win by a lightcentury. Take it or leave it, that's where we're at.
Now that I'm all done being defensive and petty, to answer the OPs question, before kids, I went ten years renting without having a dishwasher. Did not care. I most certainly would not make it a requirement, especially at the cost of paying higher rent for superfluous benefits. As you rent, get what you can afford in an area close to work. If you chose to buy, determine whether you are willing to pay the premium for the dishwasher.