How Many Coats Of Primer/Sealer Are Needed On A Flawed Wall?

Perfect,perfect, after filling any imperfections, allow to dry and then sand with a good sized flat sanding board using a fine paper. Run your hand over the areas repaired and you should not feel any high or low spots if you do build up with filler over a broader area and sand again feathering the edges. One coat of primer will be sufficient followed by one coat of quality paint(Latex). I would suggest painting the trim last.