Sewer Line Replacement. Dig/replace, pipe burst, CIPP lining?

[Todd Hannebaum]

My rental house in littleton has a few issues.  Sounds like the connection to the main sewer is offset, and the 5 feet preceding that has quite a few roots.  I believe this is out nearly at the midpoint of the street so I'm hoping the city will replace that-calling them tomorrow.

The rest of the line has a couple of sags, one is 22' long.  The entire line is beneath a concrete sidewalk unfortunately so I'm thinking digging and replacing would be too expensive.

Anyone have any suggestions or company recommendations?  I've recently learned about CIPP lining and pipe bursting but wonder if these aren't practical given the roots and sags?  

[Todd Hannebaum]

Thanks @Bill S. and @Alex Deacon!