It depends on what you want to do. Downtown DC is pretty sterile and most of the hotels around the mall are for lobbyists on per diem. If I were getting an AirBnb and didn’t want to spent all my time on the mall I would do something near DuPont or Adams Morgan and metro to the Mall from DuPont or U Street. If you want to go upscale Georgetown is quaint but you’ll have to take a bus or Uber elsewhere as there isn’t good metro access.
If you don’t want super hip nightlife and feel like saving some cash, look for places around Clarendon, Ballston, Courthouse, Virginia Square with metro access and stay in NOVA. Good mix of bars and nice restaurants that are for DINKS and singles who don’t want the edge of DC. It’s not cool but it’s fine.
DC is divided into quadrants. It ain’t the DC of the 1990s but some places remain super sketchy. In general, addresses that end in NW are fine, SW has gotten mostly better especially around Navy Yard but you should check, and NE or SE are not no-go zones but do some good checking before booking, and your locale may not be contiguous with places you want to be.