Interesting, swissman. So color seems most likely what they want and a bit surprised they accepted only 4 photos. But 4 photos is fine with me, if that's all they require. Maybe 6 is just what people generally think is required. I usually give 5: 2 of house front (close up with number + whole house), bedroom, kitchen, living room.
Those 'additional papers' add a bit to the time, but you're right, the appointment system works well.
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