I just had my sewer line checked with a camera. It is about 43 years old and made of clay. The camera showed roots and also some cracks and slightly shifted sections. Do I need to think about replacing this line and if so what should the expected cost be?
From the information you provided it would be impossible to even give you a guess as to the price. At a minimum someone would need to know the length and depth of the pipe as well as where you live (prices vary greatly by region because of union and other influences on labor costs). As to whether to replace it or not, the decision should depend on if you're having problems or not. If you aren't having drainage problems you could try using some of the chemicals that claim to remove roots from pipes (not a real green solution) and it could be fined for a very long time.
It will not be a cheap project to replace no matter what.
But to give you a starting point...my neighbor down the street...4" clay pipe...buried about 6'...apx 25' from the house to the street.....$7000 total to dig up and replace. This is in Los Angeles......and plumbers are hungry.
Even if you are on the right track, you will still get run over if you just sit there.