Perhaps the £8 didn't include the conny - or it gets done every six months (right!).
It's a funny old game really - as you may know I now employ one guy who works with me and he's a good worker but he doesn't have quite the "oomph" that I have so although he is half my age he's won't naturally go fast for a couple of hours to clear the work or get to a certain figure - and why should he?
So let's say he costs me £10/12 per hour (inc tax insurances and running costs etc)- well where as I want £30 per hour for me - I'd be happy if he earned £20 an hour rather than sat on his behind.
So I might price him up lower than me to get a commercial or a run of "marginal work".
Take it to extremes and some "gangmaster" from a large port in Lancashire (

) might think if "dab-in-hand sloppy joe" can do that house in an half an hour for £8 that'll do me.
Now you might think £35 for you to do a proper job in an hour and so both ends of the market have met.