just as a side note, hydrogen peroxide is not really stain removal, but a bleaching by adding hydrogen to the stain and making the stain appear lighter, as such its only really effective on light / cream / white carpets and does have the tendancy to slowly wear off, so would be wise not to offer it as a permanent stain removal.
I normally suggest using it simply as a cosmetic treatment to enhance the appearance of the stain, not removal, as its actually not removing anything,
Regards
steve