You are going to need MUCH more information before you or anyone else can price this job. What size sub-panel and what distance from the panel, through what conditions. Has a load calculation been done on the existing panel and the additional load to be added calculated to determine if the existing service is adequate? Will the new kitchen have electric or gas appliances? What other appliances will be installed in the kitchen? How many small appliance circuits will be installed. What will be the conditions for wiring the kitchen, will it be bare studs so like wiring a new house, or will the wires need to be fished through finished walls. Right now A "ballpark figure" would be between $1000 and $100,000. I'll say it again, There are no shortcuts! Get your information together perform a load calculation and then bid the job accurately or walk away.