Construction supervision should definitely come from the local area – flexibility is important, as some inspections need to be done precisely on time and at short notice to avoid disrupting the construction process.
It is understandable that, for cost reasons, the number of inspections should be kept low. Secure control cannot be guaranteed, for example, with only 4 inspections. Quality is often evident in the hard-to-see and quickly covered work. A basement waterproofing or external thermal insulation composite system, for instance, consists of several work steps or layers – this is difficult to inspect after completion.
From my experience, it is sensible to choose a middle way between inspections by an expert and those by the clients – provided that the expert and clients coordinate well. The expert should explain exactly which points need to be focused on. In case of doubt, phone calls and photos can provide clarity.
In a sensible combination of inspections by the expert and assessments by well-prepared clients, what is actually desired can be achieved: to avoid defects or at least detect and have them corrected early.