What is the average cost to replace a GFCI outlet?

Inquiring minds want to know: what's the typical financial outlay associated with replacing a Ground Fault Circuit Interrupter (GFCI) outlet? Given the variability of labor rates, material costs, and geographical differences, it's a question that begs for a ballpark figure. Could you shed some light on the average cost to upgrade or replace a GFCI outlet, taking into account both the cost of the outlet itself and the professional services required for installation? Understanding the financial implications upfront can help homeowners and property managers budget accordingly.