Thanks Yank however I interpreted it as (I had some dealings...

Thanks Yank however I interpreted it as (I had some dealings with this sort of engineering study on a development I did once)getting the 80% to within + or - 5% and the other 20% sort of fits within guidelines of about the same levels...a sort of this % is close enough so we know what we are spending within acceptable norms...I get what you mean and that is what I meant. An 80% detailed feasability is the accepted level for costing in other words...it is considered the standard for budgeting projects accurately within norms.
Comments?