How much a 2012 Mustang turbo kit for a V6 engine will actually cost for you will vary depending on different factors, like whether you choose a single or twin turbo kit, the quality of the kit, and whether you have an auto shop install it for you or opt to do it yourself.
If you do have your 2012 Mustang turbo kit V6 installed at an auto shop, you can usually expect to spend at least another several hundred dollars on labor costs.