How much American Dollars Does it cost to change Windows ME to Windows XP?

I have a Windows ME computer and want to upgrade it to Windows XP. Yes, i know its an old operating system which is why i want XP.How much American Dollars Does it cost to change Windows ME to Windows XP?
to upgrade your OS , you need to be sure that your rams are over 128 MB at least and your hard disk is big enough to have windows xp . I am not sure about how much it cost to install it , but it might be around $ 120.How much American Dollars Does it cost to change Windows ME to Windows XP?
Chances are , your computer is simply too old to run Windows XP.