I stayed in Natasha's studio for a month in the summer while I was researching in DC. It was perfect! The studio had everything that I needed: comfy bed, good sized kitchen with amenities, lots of storage space, TV and wifi. It was very well located on the metro line and several bus routes making it easy to get in and out of the city centre. It was a very relaxing place to base myself (with ac!) after a busy day out in the city.
Cleveland Park itself is a very pleasant and chilled area with several nice cafes, bars and restaurants - I particularly recommend Medium Rare. It is also walking distance from other popular night spots: Dupont Circle (30 mins), Adams Morgan (20 mins) and Columbia Heights (35 mins). I ran most days in Rock Creek Park, just 5 mins down the hill - a stunning and relaxing getaway in the city centre.
Natasha was very helpful, offering me clear assistance when I arrived, but then respecting my privacy after that.