you can no longer get away with 'subbing' the work out, that's no no.
Legally he should be insured by you, and that means employers liability and all the other costs that being an employer ensues.
I also do not really fear newcomers coming into the job and going WFP.
They still need trad skills, and they will be very slow learning them.
WfP also takes investment, has much higher running costs and most certainly has a certain skill level.
Knowing how to price properly is also harder for a WFP newbie, and unless they have a very good understanding of how to run a business properly a great many will fall by the wayside.
And of course, if they have invested a few grand equiping themselves with WFP, they still have to pick up the business to be able to earn this incredible income!
Have to say I read your post with a fair degree of cynicism, in just 30 hours of canvassing you picked up a shed load of really well priced work and have someone who has never done the job before earning over a £100 a day!!
Methinks the reality is very very different.
Ian