I personally do not agree with this guest's claim that the neighborhood is not safe. I have lived here and have hosted on airbnb for five years now, and have never had an incident with safety (for myself or my guests). We did convey this to the guest, but it seems she is simply uncomfortable in an urban, mixed-race neighborhood.
Like any neighborhood in the city, we do recommend our guests use street smarts like not leaving items in cars, not walking home alone late at night, etc. But any host in Washington DC, regardless of neighborhood, would recommend this to their guests.
We do have two small children, and as the unit is an in-law suite, we cannot completely isolate noise between the house and the units. We do make a point of taking the kids upstairs to the third floor by 8pm and bringing them downstairs no earlier than 8am, so as to minimize noise in the evenings and mornings. That said, we will make the fact that we have kids and that there will noise in the in-law suite clearer in our profile/write-up so folks are aware before booking with us.
Finally, we use a professional cleaner and ensure that sheets/towels are cleaned before new guests arrive.