Two halves of one city, two different lifespans.

Bay Gate Locksmith works San Francisco out of a van rather than a storefront, because a lock is bolted to a door and does not come to a counter. The van sits on Divisadero, which is not a sentimental choice: it is roughly the line where the marine air stops and the sun starts, and it puts both halves of the city within a short run. Every minute quoted on this site is measured from there. Downtown, Nob Hill and the Tenderloin 14, the Marina, Cow Hollow and Pacific Heights 15, the Mission and the Haight 16, Noe Valley, the Castro and Bernal Heights 17, the Richmond 18, SoMa and Mission Bay 19, the Sunset 21, the Bayview, Excelsior and Portola 24. Over the county line: Daly City 27, Colma 28, Brisbane 29, South San Francisco 31, Pacifica 34. Eighteen minutes is the average. Calls are answered 24 hours, nights, weekends and holidays included.

The idea this business runs on takes one line: in this city a lock is far more likely to be killed by the weather than by anybody trying to get past it. Through the Golden Gate the marine air comes in year round, and on the western half of the peninsula it carries salt onto every piece of door hardware facing the street. Corrosion works on the inside of a cylinder, on pins and springs whose whole working tolerance is a fraction of a millimetre, so the failure arrives on a schedule rather than all at once. The key gets stiff in winter. Then it turns halfway and wants a jiggle, and every household invents its own private technique instead of calling anyone. Then the bolt stops reaching the strike, the door gets left on the latch, and a maintenance problem has quietly become a security one. Then one cold morning the blade snaps in the keyway. Four miles east, in the Mission or on Bernal Hill, the identical lock on an identical door is unremarkable at twenty years. Two neighbourhoods, one city, two entirely different lifespans, and almost nobody tells you which one you bought hardware for.

Pricing follows the same list every time and the $89 visit sits inside every figure. A house lockout is $135 to $249, a car lockout $115 to $219, a business lockout $155 to $279, post break-in repair $195 to $469. A rekey is $28 to $46 per cylinder, with the second cheaper than the first because the van is already at the kerb. Replacement hardware runs $125 to $319, a keypad or smart lock $185 to $469, a safe opening $215 to $559. On the commercial side, exit devices are $299 to $769 per door, access control $165 to $439, storefront and grille locks $169 to $479, and master key systems are walked and counted on site before a figure is given. A car key is $175 to $429, a vehicle fob $99 to $205, an ignition $189 to $449, motorcycle keys $119 to $275. Arriving between 8pm and midnight adds $55 and between midnight and 7am adds $95, both counted in before you agree, so a late job moves up inside its range and never past the top of it. What is not on this list is anything wired: buzzers, intercoms and elevator controls belong to a different trade.