This refers to the point of view a client might have about a project and how it is compared to what is being considered a similar completed project and why they may need more of something or not be allowed to do something the other project was allowed to do…. Really it is they didn’t have to do what your saying I need to do, why didn’t they have to do it? Are you sure I even need to do it?
This happens more often than you would think, especially for first time builders or clients who are venturing into a new business and are not aware of the current codes for that business or building type and base things on what they have seen at other “similar” establishments. Is is by no means a bad way to begin, precedent for design was ingrained so much throughout school that if a client came to me with no idea of what they wanted to do, no general vision, I would think they had not given the project serious thought and that the project may go no where.
But in having a vision or wanting things to be a certain way, you need to allow yourself to be flexible or at least know that most cases are not the same and just because your neighbor was able to do it doesn’t mean you can or should. Codes change, so depending on how old the comparable project is, it may be grandfathered in or the site may be zoned differently per local code and that project allowed more space or have a different occupancy and be allowed to be a certain type of business.
Good news though, more and more clients are getting architects, engineers, designers involved earlier on. Doing pre-design work, checking on feasibility of the site to do what they want it to do, especially when doing additions to the building or changing its use before purchasing a site or building.
I would just suggest getting someone who knows and would be able to carry the project forward to aid in the selection of a site before moving forward and present you options of what could be possible for the project.