Seems that firms in San Francisco are having trouble finding janitors, and those to staff many other lower paying jobs, because of the lack of affordable housing within a one to two hour commute to the city. One begins to appreciate the severity of the situation when it's noted that many $50,000 "entry level" jobs present the same problem.
Doubtless, San Francisco's lack of land for housing is exacerbated by the Pacific, just to its left. But many states and cities - particularly San Francisco and California - have created much of their own problem, with "open space" regulations (areas where one cannot build), aggressive building codes, and recently a host of "green" mandates - all driving up the price of housing.
For instance, quite recently California has mandated that all new housing include a solar power system, adding some thousands of dollars to the cost of each house. Some communities require a bicycle or two be included with the house (even, one supposes, if sold to the handicapped).
It is certainly nice to have lots of green space around your residential neighborhood (particularly if you owned the house when the land was set aside - quite a nice bump in your property value, accomplished solely by legislation). Much else that goes into codes - minimum house sizes, height restrictions, minimum set-backs; restrictions on adding extra buildings (like a small apartment) to the back of your lot - make life more pleasant (for those already there), and property generally more valuable. And the rent higher. But the downside is that everyone working in the area needs a higher income to afford to live, or to pay one back for a couple or three hour commute. So when you restrict the availability of, or drive up the price of, housing, be aware that you will also pay more for haircuts, and landscaping, and sandwiches - and janitors.
As Hayek noted, there are few solutions - only trade-offs.