How much will a turbocharger or supercharger effect fuel efficiency?

John questioned:

For those of you that have any upgrade in their car, how much is your fuel efficiency effected? If I buy an RSX or a Celica and opt for any selection how much will my fixed 26 mpg and 28 mpg respectively be effected by each upgrade. I be with you that more fuel will of course be looked-for. But just so how much for the average handbook?

What to do with two cars to get a lower payment?

lifefairy004 questioned:

I have two cars and I owe 8,000 on a 2002 completely-loaded mazda protege and then I owe 17000 + have a 2005 completely load toyota celica. I really want to simplify equipment and get a cheaper car payment. Its kinda of hard for me now to keep up with the maintance. I would like some opitions additional then sell the mazda personally and trade in the celica. I was thought about export a used car and then trading both of them at the same time. Delight give me some partaking.