Landscaping Last Spring

Last spring we had the front walk replaced. The guy did it cheap and we got exactly what we paid for. I cleaned up the mess he left and did the landscaping. I was disappointed with his work. The project could have been better if our interests had been primary.
When I estimate a job I try to include every last detail and then assume there will be other unknowns to answer. I am not cheap. If a project is underbid it follows that the job done will be underdone. The idea is to put every detail out there in the planning stage. Then negotiate the final details. But make sure the end result, the actual work is sufficient.
When I step on the sidewalk I am reminded of my dissatisfaction. But wait! We got what we paid for. Maybe my dissatisfaction is a result of feeling the guy did not care enough to consider we wanted something better than crap. All we had to go on was the assumption that...? Nothing in writing, no kind of representation other than 'sidewalk here'. I admit the person at fault is me. I allowed this work to be done despite feeling the project was out of control.
How about this: He presents a written, detailed project proposal with a price that reflects a "done good jobby". Then what happens is the wife and I come to understand there is more to the project than meets the eye. In my case I could counter propose to do the site work myself and we could negotiate the finer points. The result is that maybe he could have gotten a little more money and expended less effort doing the work. More importantly the actual concrete on the ground would be properly done, which it is not now, hence my dissatisfaction. The fact that it was cheap does not help one bit.