In This Chapter
It’s not just you – estimating is seriously tricky
The huge value of historical data
Three cases when you’re unsure – best case, worst case, most likely
Estimating is notoriously difficult … in most industry areas anyway. If you find that estimating to be a problem you needn’t feel lonely. Some areas, such as IT, have a few techniques to help, but even there you’ll often find limitations. An exception is the construction industry. If you ask for an estimate for an extension on your home, a builder will come back with the total cost remarkably quickly. So how does he do that when most people struggle for ages with project estimates?
The answer to the building estimates question is rather simple. Your local builder looks at the different elements needed for the extension, and then he looks up the estimates in a commercially available book. For each item the book gives a unit, such as a square metre, and then the cost for materials, labour and total. ...