There two steps need to follow to enable compare feature
Enable Compare Feature
First need to enable compare to do this navigate WordPress admin menu => Classified Listing => Settings => General now check the Enable Compare also set the compare limit. Hoe many ads want to show in compare list in front end view.
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Set Default Page
Now set default compare page from Classified Listing => Settings => Advanced => Page setup
This is just a blank page no need any shortcode
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Front End view
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Compare ads view
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