so our new house (built in '83) has textured walls in every room and some strange paint choices to boot. we decided to tackle the guestroom which was a demin blue color with a deep texture (that is curiously a totally different texture than the other 2 BRs). after priming with kills2 and painting a lighter blue flat latex, i found that the whole job could be scratched off with a fingernail. areas that i had taped off will peel down to the bare texture (i.e. through both my paint and the existing paint job). it appears that the previous owners did a plaster coat of texture and did not prime before painting. should i scrape everything off and start anew? how would i go about doing so? should i just hire a pro?