Our old house has plaster walls that were painted , by a previous owner, with cheap paint that is now peeling off in TINY chips. We would like to resurface the walls using a product that adheres as a sticky mesh and then is skim coated with plaster. How the heck do we get the old paint off of the walls so the new plaster will adhere? We have tried scraping, sand paaper, and an expensive product that was supposed to pull the paint off in big sections using a gloppy substance and paper. None of them worked as the room is very large. HELP!