Were you asked to do something or were you asked if doing something is a good idea?
If you were asked to do something then fucking do it. Any sticker shock is the CTOs problem to explain.
Time to bring Goodwin's law out.
Just because you are a guard at a prison, doesn't mean that saying "I was just following orders" is a good defense. It is YOUR job to know details and question things that come out of people's mouths to determine if they are good for YOUR company. Many times the answer is, yes it is a good idea - you don 't have to pay for upgrades, maintenance, or other things people always seem to forget about... Other times, keeping things in house is where you want to be. You should be able to find out what is correct for your organization and make sure that is what happens.