If I may, I would like to nominate the building at the southeast corner of Broadview and Danforth for this dubious honour. It was once a bank branch, now it is a real estate office. Somewhere along the line, a top floor was added to the structure, using only crude cinder blocks, and there are steel beams sticking up one storey above the addition. You have to see it to believe it. I don't want to waste efforts at this time with a picture of it. Maybe some other time.
I am sure many of you have seen the mess. I wish this sort of savagery could be prevented.