Word to those trying to sell... do not pay anthing up-front.
It is an "advertising fee" for $500 or more, yet you can do the same thing through most realtors for about 10% of that. You will STILL need to pay escrow fees and commissions, so your best bet is to avoid places like RII Stroman and SleeMyTimeshareNow.com and go with a local broker.
Also, if you paid $12000 for a timeshare 20 years ago and think it's worth that now, try 20-25% of that. In other words, if you are going to buy a timeshare, don't buy from the developer, buy used.