Hi.
Lots of security products make a promotions for 3-12months. Why don't you make Avast Pro. licence key for promotion? as 3 month avira key, 6 months Norton etc.....
avast! Home already gives almost the same protection, full automatic update capabilities and so on. You don't need a promotion. Btw, Norton doesn't have a free verison, Avira Free has significant restrictions such as lack of web protection, very poor updates, etc. You got the point i think.