Remodeling in stages can be a mistake if you don’t have an overall plan that does not change. The plan must show the entire house and not just one room at a time. Otherwise it is easy to end up with incomplete ideas, which leads to contractors guessing what you wanted to achieve.
Having the design done by one firm and the building done by another can also lead to problems, because the contractor may not have the entire picture. Details that have not yet been firmed up are always left off the working prints, so the contractor must make assumptions, which may or may not be correct. The contractor will usually assume missing details are meant to match the existing styles or materials, unless they are told differently.
For instance, perhaps a homeowner is having an addition built onto the house now, and is planning on having a new roof in a different material put on the entire house the following year. In that case, it would make sense to roof the addition with the new material. But this is the kind of detail often left off the prints, so unless you tell your contractor your plans for next year, they will assume that the roofing material on the addition should match the existing roof.
One way to avoid the problem of contractors having an incomplete picture is to use the same company to design and build. You should also make sure all changes and missing details are written in a change order or amendment to the contract. However, not all missing details will be caught before the project starts. Make sure you have open communication with your contractor in writing, via email or fax, for updates and clarifications.