Different paints have different base solvents. Most of the ones that the Eco Home Centre stock are water based, however their are a few that are based on natural oils and solvents. For the removal of old paints and varnishes the best options are available from Eco-Solutions. These are virtually VOC free, require no PPE (protective equipment), are really effective and give off no eye-watering fumes! They also make a graffiti paint remover and also a great product for reviving old solid paint brushes. For cleaning brushes immediately after use use Auro Plant Soap. This can also be used for cleaning down walls before painting