It's probably best to ask this forum if you could allow people to have image banners, and you as the advertiser might need to pay to unlock this possible feature for users. It would be great if you were just allowed to take over signatures directly, so you could change things on your whim. This could be another source of income for the forum, just don't know how well it works with their current banner ads. Also consider that the one with the sig should have some experience in your product/service and like it. To me it seems some want cheaper marketing, but they don't know how to get results.