Need help creating a formula thats able to do multiple things

[lrdsgrrsqt]

Hello everyone!
I was wondering you guys could help me out with creating a formula with an excel sheet that I've been having trouble with.

So this is what I need:

1. If "TCG low price" is greater than or equal to 26, multiply it by .70 and put it in in "Offer" column
2. Find a way to replace multiple numbers is "Offer" column.

For example, I need to replace the number 1, with .25,and number 2 with 1 and so on.

Here is the think if you guys want to download the sheet:

Dropbox

www.dropbox.com

Thank you guys for your help!

 

[lrdsgrrsqt]

So far I have this

=IF(E2>=26,E2*0.7)