Matt and Charlotte Goodsall brightened a once-frumpy guesthouse into a place that feels as current as it is friendly. The conjoined brick townhouses are historic, so no lift is permitted, but everything is updated with slate-and-white paint, fresh curtains, and touches such as bedside reading lights. If you have a first-floor room on the front, you’ll have a small balcony over busy Ebury Street; in the quieter back, you’ll overlook the cute flower garden. Only three rooms have their own bathrooms; the rest share. A basement room is larger than the others but has no view. The Lime Tree is popular so the owners have no need to discount for longer stays.