After spending weeks scraping paint from my kitchen walls that cracked I can now see there was no mist coat. I have taken it back to plastered walls but the plaster does have dents, waves, cuts and its not ideal for painting really. I have a limited budget but I am determined to do what I can to the best of my ability. I can't afford lining paper which would be a good solution. Do I fill with polyfiller or is there a better solution for me? Around light switches etc it is very bumpy and uneven? For my mist coat do I water down armstead contract mat?