It took me about 1 hour to remove a border from one of our bedrooms (it had been up about 10 years). I used the Gel version. Now I am removing wallpaper from another room using the DIF liquid concentrate. Both worked great. I found that for each removal process I need to score the wallpaper and spray and then remove the top layer of the wallpaper. Then, I spray again and easily removed the remaining paper and glue. I love this stuff.