We have learned that since they have been required to scrub and flush and camera and map the lines, they have seen a statistical relationship between laterals installed after the main line was in, versus those laterals originally installed with the construction.
This is believed to be caused by soil settlement issues due to the disturbance from undermining the pipe in a small area for the saddle attachment work.
This has now added a new factor to the quirkiness, sometimes they want the area under pipe to be tamped and backfilled, other times they want it shaved by hand to smooth non disturbed flat area then slurry placed up to the springline, sometimes they want the saddle tee to be wrapped in plastic after greasing the bolts, sometimes the slurry goes over the pipe....once you get the tee figured out, the four inch sdr-35 lateral material goes pretty smoothly with not so much discussion, and there is always a need for a line in the sand cleanout at the property line, and occasionally they want a anti backflow valve with a relief path if you are below the manhole top.
Be open minded, and of course be safe. And you may want to pay for a camera crawler with distance measure for two reasons:
to locate a section to dig where there is no butt joint in the mainline (around here increasing a patch can notably effect the cost due to more rules on fixing asphalt and road base)
and
to document as found conditions to limit your applied responsibility