I agree it's perhaps not the best time to start up, but it's not the worst either. I don't think there is ever a time that is totally unsuitable.
Granted people are cancelling, and switching to every two months, but there is still, and always will be, work out there.
If you are prepared to go out every evening for at least 2-3 hours and knock on doors, you will build up a round. You may have to knock on 30-40 doors to get one job, but if you keep at it, and knock on another 30-40 doors, you'll get another. Three jobs and you've got about £30-£45 worth of work. Do that each evening for a week (say four days) and you've got £120-£180 worth of work. That's enough for one day, for starters. You need 20 days for a full round, that's 20 weeks canvassing, or about 5 months.
I can do it, you can do it, anyone can do it, you just need to keep focussed and don't lose heart.
Even if it took you twice as long as I've said, you still get a full round in under a year - if you've got what it takes to stick at it.