No I've only encountered timewasters when I advertised for canvassers on Gumtree in the past.
Did you try advertising anywhere else?
No.
Of just a couple that contacted me I can recall one fella emailed to give me his terms and how much he would be prepared to canvass for, rather than what I had advertised for. Which was equivalent of buying an established round. He must of thought I was very green.
Then another I met who was in his 50's with plenty of experience but unemployed seemed promising.
I spent time with him going through everything, pricing jobs etc. who appeared keen but seemingly disappeared into thin air shortly afterwards. Mind you he was an ex timeshare salesman so not entirely surprised.
In the end myself and mrs did a leaflet and canvassing campaign when time allowed and it seemed to work out ok.
To be honest 8 weekly a week isn't very long to advertise, and my experience may not be the same for everybody and it was several years ago.
Just be prepared to sort the wheat from the chaff and maybe to be frustrated at times also.