I do not post very often, but read the posts as often as I can. I am a Right of Way Agent and was looking for information about repairing farm drainage tiles. I came across this site and they have a worksheet to help calculate costs. It's is in Excel and you can change fields to meet your needs. Thought of you all and people just getting started on an easy to follow worksheet. So hope this will help some of you. Springfield Plastics Inc. Agricultural Drainage When you open look for contractor cost worksheet on right hand side of page.