I supervised the deliveries of Yellow Pages across parts of Suffolk, Essex and Cambridgeshire for several yerars, as well as delivering thousands of them myself. I've also delivered Thomson Business Pages, Thomson Local directories and BT Phone Books. On many of those occasions I was working alongside people who also delivered leaflets and/or who ran their own leaflet distribution businesses.
Firms like Deya, who had the contract for delivering Yellow Pages, were pretty good at adjusting their pay rates to suit the conditions on individual rounds. (Indeed, part of my job was to review those rates and to recommend any changes I thought necessary). So, for example, the rate paid 'per directory' for delivering in rural areas (where farms could be well spread out and with long drives) was several times higher than for delivering to housing estates (where it only takes a few seconds to get from one door to the next one). Deya tried to ensure that anyone working for them could achieve the National Minimum Wage, even though the delivery staff were all self-employed (and therefore not covered by the NMW legislation anyway). In practice the work would pay around the National Minimum Wage in some areas but perhaps 20% higher in others.
Other firms I've worked for weren't as good at adjusting their rates to suit local conditions, resulting in some people only getting around half the NMW in rural areas but perhaps double the NMW within towns. (Again, the deliverers were all self-employed, so the companies weren't operating illegally if they paid less than the NMW).
I've looked at the rates offered for delivering leaflets by several firms. With some I find it hard to see how the NMW can be achieved but with others (based upon my own experience of how long it takes to cover different types of areas) I'd be confident that, at current rates, I could achieve at least £10 per hour and possibly over £12 per hour.
As well as the directory deliveries, I've actually delivered some leaflets as well but they were always one-off jobs (such as working on behalf of a housing developer who wanted to advertise a public consultation process about the proposed development of a new housing estate). The rates for those jobs were always a fixed fee to cover the entire area where leaflets were to be delivered but I ended up receiving well over the NMW for the number of hours I'd worked.