New answers tagged primer
You can apply a water-based finish over old alkyd paint as long as it is thoroughly de-glossed and clean. If it is steel, top quality grey or red-oxide metal primer (as Ben suggests) followed by top shelf exterior gloss paint. Contrary to what I often see/hear, using top quality paint and top quality applicators (brushes and rollers) makes a huge difference ...
If the prior owner used caulk, and they were really dumb and didn't use paintable latex caulk, then its possible that this would be the result. Regardless, obviously the paint isn't taking properly here - so yes, the answer here is get a quart of primer go over the edges with a brush, let it dry, and redo the corners.
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