best way to quickly remove stubborn old backing paper of vinyl wallpaper

Put washing up liquid into a bucket of warm water .brush on to wall leave for about 30 seconds and then scrap off with scraper.repeat over all paper

score the paper all over with a blade of some kind, then soak with water a few times, then steam off and that should do it a treat

A lot of trades will tell you a steamer is good! I personaly find them slow... I use a pump garden sprayer with warm water, soak your walls (mind your switches) and leave for 30 min. Use bladed scraper to remove the paper..

Strong arms warm water perseverance