The SW1 stock around Harrods is recent new-build. ONS records 77% flats, 23% houses and 3,077 households in Knightsbridge.
Private renting sits at 60% and owner-occupation at 35%; the first group books mattress cleaning at short notice, the second plans it.
Knightsbridge substrates run to with metal stud partitions between rooms, over dot-and-dab plasterboard over blockwork — where 35% owner-occupation means the same home is booked again rather than a new tenant each year. Nothing is drilled until the wall has been sounded, because in SW1, short screws that grip only the board and slowly lever it off the dabs — which is why Westminster City Council kerb rules get settled before the van is loaded is the mistake that costs a SW1 customer twice.
Two streets can behave very differently in Knightsbridge: harrods, embassies and some of the most valuable apartments in Europe on the park's south edge. The quote reflects the street the job is actually on. Knightsbridge sits inside the Congestion Charge zone as well as ULEZ, so both are itemised on the quote rather than absorbed into an hourly rate.
Getting to the door matters as much as the job: concierge sign-in, booked service lifts, and Brompton Road red-route loading windows. Knightsbridge (Piccadilly) is the nearest station, and one technician with a portable extraction machine and air mover on a single household booking; two technicians on HMO, student accommodation and serviced-apartment rounds where six or more mattresses are cleaned in a day.