Great Boutique Hotel on Rhode Island Ave.
In the northern part of Washington DC, the Helix is easy to miss because it blends in with the neighborhood. Because of the subtlety, it's a great place to stay while in DC. It's like home, but when you go in, it's pure luxury. Make sure you check in before 5, so you can mingle with the complementary wine tasting. The have their own patio where you can go out and enjoy a cocktail and smoke a cigar. 
If you have a pet,no problem, the Helix is pet friendly at no extra charge. The restaurant is great for appetizers and breakfast, but search for dinner elsewhere. There are some great restaurants around the corner within walking distance.