Check carefully at the extreme bottom edge of the door panel - as low as you can get - my Golf had several screws along the bottom which need to come off - the Polo of course is an inferior grade and may well not enjoy such robust fastenings.
Good luck...
Peccavi
August 2009
Just generalising but you'll have to remove the arm rest, window winder and door pull first....if you are sure there are no visible screws, then the panel is held on by poppers - which can be (carefully) released by sliding a broad blade implement under the door card and prising up.
John
August 2009
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