What is the "cost" of locally grown food?

Eight dollars for a dozen eggs, and $3.90 for a pound of peaches, if you can get them:

Getting fruits and vegetables only from local farms necessarily limits variety—few crops are available everywhere all the time—and it doesn't come cheap. Economies of scale apply even to produce.

Urbanization makes possible variety and low prices.  It also eliminates what Stewart Brand (video below) calls that "poverty trap" and "ecological disaster" of subsistence farming.