When flushing the toilet , the water would backup in the bowl, but not quite overflow. Hillcrest came, used a snake,said they found nothing, & said it was a defective toilet. They sent another plumber out a few days later, who ran another auger, & said there was no blockage, just a venting problem. Then the boss came out & said there is a possible dip in the pipe & a camera should be run , for a 3rd call.
In the end, City of Vancouver sewer dep't ran a camera & auger & within a few minutes said it was tree roots blocking the pipe. I am disappointed that Hillcrest was so certain on their first 2 calls that it was NOT a blockage.