Nick to be honest the fact you canvassed grantham last year is irrelevant. I have recanvassed areas I have done for myself after a few months and always come out with more work. 300 in grantham is the tip of the iceberg... I did an estate last week that has been marketed very hard for the last three years and come out with 120 quids worth of work in under 3 hours.
Just a quick note to everyone who emailed, just about to sit down and reply to you all....