Based on Travis' first post in this thread, it seems like they were due to pay us in mid-October for a 90-day quarter. If they pay us now after at least four contacts, what is the time period before they are due to pay again? It seems that if they pay us $150 for three months of advertising, it should expire in mid-January since we have kept their ad running 24/7 since it was due. While that may seem unfair to some and we do not want to lose them as advertisers, I recommend that once we decide when their ad expires we send them a formal letter stating the coverage period for their ad and the terms for renewal payment (I would recommend we apply no more than a 15-day grace period on ad payments). In essence, we need an "advertiser contract document."
I would also recommend that we create and offer a one-year sidebar ad rate of $500 (versus $600 if paid quarterly).