I am really frustrated now.
I've tried it twice on my first savegame. I did all with the same character but turned off my console in between and used fast travel.
Today I tried it on the latest patch (1.09) with a fresh savegame. So I deleted my old save files and started a new game.
I did missions to that point where you are required to recruit a construction worker.
As soon as I have recruited him I started to do the paste ups. All in one sitting without pauses. Took me about 2.5h.
But even with this method the trophy didn't pop.
It is so annoying!!!