Post your ad, immediately delete it from your account and wait for a few hours. Go back to your account, select the ad and push the "UNDELETE" button. This works especially well for pet posters because animal activist thugs monitor the ads as they come up, Meaning certain ads will only stay up for a minute or two if on the top of the 1st page. If you can get to the 2nd page of listings, your ad will stay up longer. When you "UNDELETE", your ad goes to where it would have been when you originally posted it, hours before. People searching for something you are adopting out will still see/search out your ad,
but flaggers have moved on to the newer posted ads. It works!