Our contracts are typically a "cost-plus" format which requires a lot of trust from all parties involved. We deliver value from the initial planning stage but also strive for constant value engineering through the project. This is an example where the plans called for a specific pocket door track and roller for every location. After we finalized the door slab quotes we asked the supplier for door weight by location. Using this info we were able to propose appropriately rated tracks by location in the same high quality brand of hardware. This resulted in a total potential savings of $7,470...the client accepted the substitution.
While it's sometimes frustrating, the opening line of the response is often "it depends." When a material changes during construction it's important to be clear on the detailing so a well intentioned "upgrade" doesn't become a detractor to the overall scheme of design. This is an example of a stucco wall the client requested be changed to mahogany. Since there were no existing plan details for wood siding, we provided these sketches to the architect for options on corner detailing ranging from lowest labor intensive to most labor intensive.
Nothing kills quality as much as a misunderstanding during the bid phase. In addition to collecting and reviewing subcontractor bids, we do our own take-offs and share them with subs after obtaining their proposals. We do this to make sure each sub has included all areas, details and phases for their portion of work. If they've provided a lump sum proposal and discover a take-off discrepancy during installation it's too late too change course and someone has to compromise. We try to prevent this and at the same time we get to calculate and monitor price/unit and ensure fair pricing vs. expected quality.