George has one good idea.
I'm probably not understanding the problem. If there is an ad posted wouldn't it be obvious it is an ad, and I don't think making its links broken will stop and ad.
Here is another idea. I've seen sites that require you to type a sequence of letters shown to you in an image, to keep automatic software from going through the site. Maybe that is what you need. I've found a could forums when doing general internet searches that had that feature to be able to search. I didn't understand why a search would need that.
I'm probably not understanding the problem. If there is an ad posted wouldn't it be obvious it is an ad, and I don't think making its links broken will stop and ad.
Here is another idea. I've seen sites that require you to type a sequence of letters shown to you in an image, to keep automatic software from going through the site. Maybe that is what you need. I've found a could forums when doing general internet searches that had that feature to be able to search. I didn't understand why a search would need that.