I’ve been a master plumber for over four decades. Recently a woman hired me to do her drain, waste and vent riser diagram, a water-line drawing to ensure that all fixtures would get plenty of water, and her natural gas riser diagram. Her local building department requires these to obtain a building permit.

I included notes with each drawing when I emailed them to her. She often responded with a few questions. I uncovered a potential problem in her specifications with respect to her water heater. I felt it was too small and suggested installing a tankless heater in her new home.

This woman asked if I’d be kind enough to review a bid she received from a plumber to do the work. I was stunned when I studied it. The quote only covered the plumbing drain pipes and water lines that would be under the slab of the house.

This is just a two-bath house with a small half-bath. The plumber’s quote was for $38,000. I almost fell out of my chair. I did a very fast estimate of materials. I felt all the pipes and fittings could be purchased for $2,500. Three thousand dollars of washed gravel would be needed to fill around the pipes. I then estimated it would take two experienced plumbers about four days, at most, to do the work.

I suggested that I create a set of specifications for the plumbing job that would require the plumbers to break down their bids into labor and materials. They would also have to list the hourly rate a worker is paid in case a change order is requested.

Creating specifications is not that hard for many jobs. You can do it yourself by getting your inspiration from the installation instructions for the products you want installed in your home. Try it. Pick out a specific window, then go read the installation instructions. All the important steps required to ensure that the window will perform well are in the instructions. Don’t assume that any contractor is going to always do what’s right. Your contract needs to simply say that the job is going to be done according to the specifications used to bid the work.

The day after my email exchange with the woman, I had a conversation with my friend Wayne, a retired chiropractor. He shared a short story about a patient who came in years ago crying. He thought she was in terrible pain, but the tears had to do with her getting ripped off by a contractor.

This woman was wealthy. More often than not, contractors took advantage of her by overcharging her. She needed a simple screened-in porch built for an upcoming party. This woman trusted the contractor and gave him a large sum of money up front to purchase materials. You should never do this. The only time a deposit like this is required is if it’s for custom materials that can’t be returned.

Calls to the contractor were not being answered. She was in tears because she thought the porch would never get done in time for the party. Wayne had another patient who was a carpenter. The carpenter got the job, completed it in two weeks, and the woman was happy as a clam.

But it didn’t end there. The woman was so happy, she continued to use the carpenter for all sorts of projects. He continued to treat her fairly. She saw that his truck was in disrepair and bought him a new one. She also found out that he didn’t have any savings plan for his retirement. She helped him start one and contributed to it with each job he did for her. True story.

The woman wanted to find a reliable and trustworthy person, and once she did, she treated him fairly — just as you want to be treated fairly by the contractor. It’s the golden rule in reality. Follow it, and magic might happen with all your future jobs.