Mark,
Good idea!
Never had anything like this when I started. Mind you probably wouldn't have bought it!
Too tight fisted. Could buy a squeege, washer, scrim and sill cloth for that and watch a few others in town then try myself!!
However, I don't believe that is the right attitude!! For £20 your DVD is, I hope, full of advise on all aspects of the trade which would take years to learn. With the help of the DVD a new person to our trade may be able to learn faster and get up to a good rate quicker and soon earn back the £20 investment!
Good luck to you!
David