We had a very pleasant stay at Cheng's house in Koiwa! The location is a bit far from the Koiwa station (about 20 minute on foot) but easily accessible via a bus, and you can get most of the stuff you would need for daily life in the neighborhood (there are quite a few supermarkets and shops of various sizes, local restaurants, pharmacies within 10 minutes walking distance). We spent most of our time in the kitchen-dining-living room on the second floor, and it got everything we needed for our long stay. We loved the fact that the room and the ones on the third floor) get a lot of natural light during the day. Cheng was an extremely generous, accommodating host and responded to our inquiries and requests right away at all times. We highly recommend the place!!