Nothing you'll ever notice in a 30' pad with a 6 foot rule......... and a
tightly stretched line. How many houses do you suppose are set out this
way?


Not too many anymore - most are shot with a transit. And the ones
that were set with a line level could be shot with a transit and you
would see the error. They will get you "kinda close" but every time I
ever had to use a string level, I would always take several readings,
sliding the level back and forth to the same position, re-read, etc.
Most line levels are only about 2 or 3 inches long, and most are made
cheaply, and they are surely not something I would set a house with.
If a good transit is not available - the water hose would work,
although cumbersome.
Ken.