A google search shows some very mixed information ("key the surface"/"don't, whatever you do key the surface") so I thought I'd ask here to see if anyone has any first or good second-hand experience.
This is a white plastic window frame which overlooks our garden and is a highly conspicuous blight since it's a natural draw for the eye...we want to minimise the impact by painting the frame a dull colour compatible with the brickwork, the neighbour has already given his blessing.
Would keying be best? And/or are there specific primers which enhance adhesion? A non gloss finish would be prefered.
Many thanks for any insights....