For example, the conversion of a listed building may result in a series of unknown and unforeseen costs over and above that which may have been reasonably predicted.
Er enghraifft, gallai addasu adeiladu rhestredig arwain at gyfres o gostau anhysbys ac anrhagweledig yn ychwanegol at yr hyn y gellid bod wedi’u rhagweld yn rhesymol.