that thing looks like its from the 1970's.......central vac is the way to go...........
I too almost got into something like this in High School, they sent me a letter saying I can earn $17.50 an hour/base pay with the potential to earn more....so I went to check it out and sat there for 4 hours while they showed me how to sell knives(no where in the letter was it about selling knives).....oh these weren't just any knives, they were cutco knives, can slice and dice thru anything without the blade ever breaking or getting dull....same setup as the vacuums, start with your family, get referrals from each person, they recommended you get 5 from each and then your list goes from there......needless to say, I lasted the first day of training and didn't go back for the last 2........now i'm in the retail business, go figure..........Your son is in the right direction and seems like an ambitious kid, thats great.....Its all a learning experience and if anything it'll give your son interpersonal skills....dealing with people and communicating is an invaluable quality.