@osa
The % is based on actual cost not on budget cost,which comes out when the works is tendered and the contrctact is awarded all thev way to final cost after implimentation. since the payments is made in stages(cap 5....) you will be able to balance out as works goes on hence you are covered in overpricing. any malpractice on the side of the architect or QS your remedy lies with the registration body BORAQ so long you paid the statutory consutancy fees and there is a contrct between the two parties
depending on the size of the project there are other consultants involved especially service engineers though a structural engineer is almost a must you need to budget for them from the onset
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