Some more tips. Aside from making your ad look nice, be informative. Tell exactly what the state is of your items. If there is damage, say so. If there is no damage, also say so! If it´s new, used, extra bit etc etc.
people like to know exactly what they buy. It makes them feel safer. Also less trouble after they recieve their purchase.
Make it sound fun and use different words to describe your items. (include playmo bil playmobeel klickies klicky etc etc) and mention the theme where your klickies come from. Your ad needs to be findable, so use many search words in your ad.