Colors not matching in print!

I've done two projects in cs. Saved as a .ai file. Looked great on
screen, even printed a trial version on personal printer. The first
one, a band flyer, I had printed at Kinko's. The second, a lovely
postcard sized invite done through vistaprint. All seemed ready to
roll.

BOTH of them printed in a "faded" fashion. Such a bummer. Looked as if
a film were over them. Still nice a crisp but, not up front and bold.

What the heck do I do to remedy this?

Thanks in advance.