After evicting my downstairs tenant from my duplex, I had to renovate the bathroom. I wanted to do as little as possible but we knew there was water damage in the flooring. Long story short it's been a full remodel down to the studs. During this remodel the plumber has discovered that the big cast iron waste pipe from upstairs has holes in it. They are fairly large holes. One is maybe 3 inches top to bottom and one inch wide at the largest part. The other hole is more like 1-2 inches round. They are in a big heavy cast iron pipe and right above and below the bell part. My plumber wants to cut open the floor and walls in the upstairs apartment (which is currently rented) in order to cut out that whole section of the pipe. While I appreciate his wanting to 'do the job right' (I truly respect that), I can't help but wonder if we couldn't find some sort of creative way to patch these holes? Maybe there is some product out there that will adhere and seal to a cast iron pipe? Some sort of tape and/or epoxy?  I'm not an expert at all in this area, so I'm hoping somebody from the community knows a great way to deal with this that won't cost thousands of dollars??  HELP!!!