The location of the flat is perfect! What might not be clear to foreigners - like myself - is that the "5 minutes walk to Hammersmith" means "5 minutes walk to Hammersmith STATION." That is, tube station (side note: don't call it a subway there. I asked a person where the subway was, and he pointed me to a Subway sandwich shop).
Getting to and from the station is EASY and there are a lot of neat pubs and food places along the way! Do yourself a favor and buy the oyster card or a day pass if you plan to use the tube a bunch (which I recommend). it pays for itself after like 3 trips.
Michela provides breakfast which includes cereal & milk and these amazing chocolate sticks (well at least what we got, it might change from booking to booking). That was very useful and saved us some money.
The one downside is if you go in the the winter time, be prepared to be cold for a bit each time you enter the apartment. It takes about 30m or so to get comfortable :(