Rent-a-scout cannot be part of a troop fundraiser because then you may run afoul of child labor laws with kids under 14, as well as liability insurance problems. In my neck of the woods, each Rent-a-scout is a self-employed business man (good for several merit badges: American business, home repairs, painting, personal management, salesmanship, etc). They are all active Scouts, and are supposed to use some of the money to fund their Scout activities. They do go through an informal training session with two of our Scouters who happen to be businessmen. In this workshop they discuss pricing the jobs, customer satisfaction, over promising & under delivering, job scheduling versus school work, and so on.
We do require near First Class.
The advantage here is that a disabled (Scout) parent acts as the clearing house (commercial phone line needed -- paid by the Rent-a-Scouts as a whole). When a call comes in he checks his master list of which boys want to do that kind of work, what geographic areas they wish to cover, and what their hourly rate is, and are they currently available.
It is important to have the customer understand that this is not an official Scout activity. It is a private money earning venture by a group of boys that happens to be Scouts to earn money for High Adventure and Scout popcorn eating. For initial customer contact the Scouts must be a minimum of two.
Neither the troop nor the chartering sponsor can take an active role in this. It is strictly a voluntary association of self-employed young businessmen.