Seeking opinion on corroded cast iron drain pipe

[Gastronomique]

I have a 80-year-old house in Maryland. There's a drain pipe in the corner of the basement that is below the kitchen sink. The upper 2/3 of the pipe was replaced with PVC before I bought the house. The lower 1/3 is cast iron and rusting and appears quite corroded in a couple spots, but it's not leaking.
I'm going to have the cast iron portion of the pipe replaced by a plumber, and will have him insert a camera into the part of the drain pipe under the concrete foundation to check for further corrosion damage.
I have two estimates from plumbers. One proposes to cut the cast iron pipe just slightly above the foundation and replace it with PVC. The second estimate proposes to dig into the foundation, and remove the old cast iron pipe at the the hub and replace it with PVC. Both plumbers also propose to inspect the remaining cast iron pipe under the foundation with a camera.
My question is, is it much better to dig into the foundation so that the cast iron pipe can be removed at the hub? Or is it equally or almost equally good to remove it just above the foundation? I ask because the plumber who wants to remove the cast iron pipe at the hub is charging $700 more than the one who wants to cut the cast iron pipe just above the floor. The first plumber says the reason to dig into the foundation to remove the cast iron pipe at the hub is to avoid the splitting of the cast iron pipe at the seam, which does appear to be separating very slightly. But if I can save $700 by removing the pipe just above the flooring without causing problems, I would prefer that. It seems one possible way to prevent the pipe from splitting could be to clamp it tightly in three or four places along the pipe with ring clamps. That would only be temporary because once the pipe is removed and replaced, it doesn't matter if it splits or not.
Another question is, how much confidence should I have in a camera inspection of the pipe under the foundation? In your experience, if a cast iron pipe is corroded above the foundation is it also likely to be corroded under the foundation? Or not?
I'm told I'm looking at $7,000 to $10,000 to replace the entire pipe under the foundation and obviously would prefer to avoid that if possible. There is no evidence that the pipe is leaking either above or below the foundation at this time.
I welcome opinions and any suggestions you may have. See the attached photos of the corroded pipe. Thank you in advance.

 

[CT18]

There is a chance that line is having issues below the slab, but that is just a guess. You could cut just above slab and replace with PVC. I would put in a cleanout and then have someone come out with a camera and maybe they can tell what condition the below slab line is in. I would not pay that much. I would take out the concrete myself if anything. I would also get multiple quotes, seems some people are very shady nowadays. Good luck

 

[MicEd69]

You have received a great life out of your cast iron sewer lines. It is possible that once you get a thorough inspection of your sewer pipes, you may need everything replaced.

But should the cast iron sewer lines under the slab be acceptable, if you take the lower bid and find that the piping stub is indeed in too bad of shape to use, what is the extra price for the low bidder to do the same work as the higher bidder?

Another part of your decision should be how long are you expecting to remain in that house.

 

[TomFOhio]

If that pipe is just rusted on the outside of the pipe and the pipe seems solid then it could be cut with a sawzall and you
could tye in right there. But if that pipe is thin then you would be better off to take the elbow out of the ground and put
a new one in. Put in a clean out line CT suggested.

 

[Gastronomique]

I have a 80-year-old house in Maryland. There's a drain pipe in the corner of the basement that is below the kitchen sink. The upper 2/3 of the pipe was replaced with PVC before I bought the house. The lower 1/3 is cast iron and rusting and appears quite corroded in a couple spots, but it's not leaking.
I'm going to have the cast iron portion of the pipe replaced by a plumber, and will have him insert a camera into the part of the drain pipe under the concrete foundation to check for further corrosion damage.
I have two estimates from plumbers. One proposes to cut the cast iron pipe just slightly above the foundation and replace it with PVC. The second estimate proposes to dig into the foundation, and remove the old cast iron pipe at the the hub and replace it with PVC. Both plumbers also propose to inspect the remaining cast iron pipe under the foundation with a camera.
My question is, is it much better to dig into the foundation so that the cast iron pipe can be removed at the hub? Or is it equally or almost equally good to remove it just above the foundation? I ask because the plumber who wants to remove the cast iron pipe at the hub is charging $700 more than the one who wants to cut the cast iron pipe just above the floor. The first plumber says the reason to dig into the foundation to remove the cast iron pipe at the hub is to avoid the splitting of the cast iron pipe at the seam, which does appear to be separating very slightly. But if I can save $700 by removing the pipe just above the flooring without causing problems, I would prefer that. It seems one possible way to prevent the pipe from splitting could be to clamp it tightly in three or four places along the pipe with ring clamps. That would only be temporary because once the pipe is removed and replaced, it doesn't matter if it splits or not.
Another question is, how much confidence should I have in a camera inspection of the pipe under the foundation? In your experience, if a cast iron pipe is corroded above the foundation is it also likely to be corroded under the foundation? Or not?
I'm told I'm looking at $7,000 to $10,000 to replace the entire pipe under the foundation and obviously would prefer to avoid that if possible. There is no evidence that the pipe is leaking either above or below the foundation at this time.
I welcome opinions and any suggestions you may have. See the attached photos of the corroded pipe. Thank you in advance.

Thank you to all of you for your helpful suggestions. I'm going to give it some thought and try to come up with a solution. I realize there are risks either way. My main concern is the possibility of needing to replace the entire drain pipe under the slab.

If anyone has other suggestions, please keep them coming. Thanks again to all of you.