Its 2018 already and 3Ds max hasn't made the reference scaling tool easier as it is in Autocad!!!
i am an architect and i teach 3ds max to young students some times and once they get the model scale wrong they do it all over again because the scaling too does NOT work with dimensions.
please consider this , it would help a lot of people to just select a model > scale > reference that to a dimension between two vertices and its done
thank you