So there's no minimum posts? I think if there isn't a lot of people will just wear the sig/avatar and not post. Maybe consider doing just an avatar campaign that way members can join other signature that pay a decent amount whilst still promoting your business. I'd be interested in an avatar if you wanted to just do that.
Thanks for the responce, I have set a min activity, I cant offer alot, so I am happy to get whatever exposure I can.
FYI, This is not to have both sig and avatar, I am paying for just one space, whatever the user can spare, I have clarified this in OP.
Thanks.
Since I have my own signatures already, I will be using the avatar instead, for free just to help you

Top person! Thanks.