I would check with your local codes - typically you only need one GFCI per circuit in a kitchen and it is usually placed at the beginning of the circuit that feeds the remaining outlets. That being said, if you want to replace all 4 outlets you can do that as well - a GFCI will run you around $10 and depending on the electrical or general contractor you hire you will be looking at anywhere from $30-$70/hr and perhaps a general service charge for arriving at your house. All said and done, if you decide to do all 4 it should be less than an hour’s worth of work; so, based upon the figures i just gave, it would run you somewhere around $75 and up.
It does depend on your area and the person installing the outlets. Generally one GFCI outlet installed by removing an existing grounded outlet and replacing it with a GFCI outlet is: $ 125.00.
So to replace 4 outlets with GFCI outlets would run you: $325.00 - $400.00.
It depends on the area you live in of course.
$75-125 should be the price of 1 GFI outlet with a licensed electrician.