How much is tuneup costs for this engine? on 2005 Cadillac DeVille

Have not tuned engine close to 100K!
Funds are limited.
Thanks for any info.

2 answers
dealership =$400, independent shop =$300, student or a wannabe =$150, yourself =$40, satisfaction of doing it yourself...priceless
approx 300.00 labor and plugs depending on labor rate in your area. if it needs more that would be extra