Sewer pipe replacement quoted - Requesting thoughts on fair price

[Kwan Suh]

Hi guys I was wondering if I can get your thoughts.

So a local plumbing company inspected my property and found the sewer drain pipe (cast iron) rotted where where it connects to the clay pipe that goes into the floor of my basement. 

He mentioned that he has to bust up the floor to expose the cast iron pipe, remove broken Cast iron pipe, then replace it with a 4" Sch 40 PVC to connect it to the existing PVC backfill underneath the concrete floor, 

then reapply concrete to smoothen the surface. 

The quoted amount was $1,100.00 for the work and I was wondering if this is a reasonable price. 

Can I get your thoughts please? Thank you!