I stay only in budget hotels, the so-called "business hotels," and never pay more than $100 a night--and that's in central Tokyo--for a small but clean and safe room, often with breakfast included. The costs are much less in smaller cities. I'm in Matsue now, paying about ¥6000 for a business hotel with free wi-fi and breakfast.

As for food, if you can't find lunch for ¥1000 or less and dinner for ¥1500 or less, you're not really trying. (Assume about $0.01=¥1, so that ¥100 is about a dollar.)

Unless you have relatives in Hiroshima, there isn't any point in staying there for 14 days.