I checked the other postings and could not find one specifically on this issue and the questions about wax rings.

I live on the bottom floor of a 3 story condo, for only about 6 months. When the main drain of the building gets clogged by the neighbors (like with papertowels or grease most recently), my place is the first to backup because I am right next to the overflow line outside my condo. When this happens, I have seepage around the bottom of the toilet and some backup in the tub. My next door neighbors bathroom is right next to mine and they do not get toilet seepage like I do, but they do know when it backs up as she gets the backup in the tub too.

There is also drain in the common area that also backs up when this happens and floods the concrete floor by the washers.

The sewer man came out for the association when it last backed up and cleared the drain. He also looked at my toilet and said there was no issue with the wax ring and that is was supposed to seep when it backs up. Is that right? I want to know why the neighbor does not get this seepage and I do. Could it be that I need to replace my wax ring? If wax rings do leak, how much seepage should I see? Should it ever leak? Is there anyway to permanently stop it from backing up up my toilet line?

Wax rings do sometime fail and need to be replaced. The amount of leakage depends on how bad the wax ring has failed. Your commode needs to be taken up and a new ring installed, they are not suppose to leak at all so no leakage should ever be seen.
There is no way to stop it permanently from backing up in you toilet line.