Hi, You can consider using USG Joint compound (USA) or E28 Joint compound from Malaysia. They are available in 5.4kg(S$9.50/$12.50) or 28kg ($19.50/$24.50). After plastering with a tapping knife, you can sand it with either sandpaper or an electric sander once the plaster dries . Please remember to wear a face mask and safety goggle for personnal protection. All product are available from Power-J Trading Pte Ltd next to Aljunied MRT station(86 Lorong 25A Geylang S388263)