Hi,
20 customers from 10,000 is 0.2%, so from 27,000 leaflets at the same success rate is 54 more new customers.
74 new monthly customers at say £15 an average clean = £1,110 of new custom a month, and I'm pretty sure Lee's average customer spend is more than that. Plus all the extra one-off cleans like gutters and fascias.
And as Lee says new customers will still be ringing from all the leaflet drops for at least a couple of weeks or more.
Cheers,
Huw