Su is a great host - very responsive, warm, and wants to ensure your stay is a positive one. I stayed 4 days with Su, which was fine for me as I hadn’t planned to go into the city much. Around her home, there is a Tesco by foot in about 25 minutes, a park for running, soccer, tennis, within 5 minutes walk, and Hatton Cross within 15 min walk which will connect to to anywhere in the city. Her home is walkable to LHR terminal 4, (very easily!) within 15 min and from there you can take free bus or underground to any other terminals. Great place to stay for an early flight!