What's terrific about it:-- private bathroom and working washing machine, consistent, fast wifi, location close to Kew station and best Kew attractions, including Tap on the Line and Royal Botanical Garden. Only a stone's throw away from the National Archives for researchers.
What is less desirable (particularly for a longer stay): no kitchen access, and despite mini-fridge, hot plate and utensils for making tea, eating meals is extremely inconvenient, to say nothing of preparing them. (You have to wash dishes in the bathroom sink.)
Verdict: It will do in a pinch for a longer stay if other options fall through. Staying for only a few nights would be better! Location is unbeatable if you want to discover Kew and everyone in the house and online was very friendly and charming.