My suggestion:
Since the Officers, et al, are all volunteers, why not have 2 or 3 volunteers who have the responsibility to review those that are posting for the first time.
The system should be modified so that there is a 48 hour delay from the entry of the posting to its entry into the Forum.
In that time, one of the 3 volunteers can review and determine that it is "legit". If so, pass it on; if not tag it as spam.
I will throw my name into the hat as one of those reviewers.
Any other takers??
Of course, there needs to be a buy in, and some effort, buy the Officers and Web Manager.
Alternatives???