Is it a quiet little cul-de-sac???
Are there other people living in other buildings at number 18? I am pretty sure there are and whitepages backs that up.
There was a thriving business there a few short months ago, that may have had employees as well as the owner. Deliveries, couriers picking up. Business may still be operating.
The house has obviously had a lot of work done tidying up and construction, recently, if you compare the google and bing maps.
There are reports that farm labourers are on foot around the place.
Who knows what else is happening in the other properties around Sierra's home. Other businesses being run from sheds, dual occupancies, well turned out homes who may frequently have gardeners, cleaners in and out, plus dual income families commuting ...
Now it is probably "quiet" compared to real urban situations. But I think on balance though it may be busier than most suburban cul-de-sacs where many people leave in the morning and stay gone for the day, and the remainder are mostly sahps and retirees. There are people around because it is a mixed use area.