The point is trivial, you can’t give exact estimate to simplest tasks. Estimate is a distribution. Maybe normal, maybe narrow, but still it’s not a single number.
Whether you bill clients hourly or on a per project basis, a necessary step of all projects is estimating the time it will take. Not only does the client want to have an idea of how much money they will be spending, but they also need to plan around an estimated timeline. And you need to be able to ensure you have the time and resources necessary to complete the project.
Depending on a number of factors, including how much experience you have with the type of work you’re doing, if you are using subcontractors, and the information you have from the client, estimating the time for a project can be difficult. Here is the process I use when scoping the time commitment for a new project.
The first step is to identify the main project (i.e. Website Redesign), and then pinpoint the specific deliverables associated with the project. For example, upon completion of the redesign, you will be providing the client with a newly designed website by FTPing the site files and sending the client a CD or USB drive with the working files.
Break It Down
Next, I take the project and break it down into simple tasks separated by component – the more specific the better – that will get us to the deliverables. Here is an example of what the tasks may look like:
The next step is to estimate time for each task, rounding up. If you are using subcontractors, you will need to get their time estimates first and work them into your time. Then take the total time for all of the tasks and add in a buffer. The buffer can be anything, although I usually stick with a 10-25% addition. This allows for any unexpected situations or challenges that arise.
Things to Keep in Mind
The more time estimates you do, the more accurate you will be. As you create your own formula, some other factors you may want to consider include:
Another trivial idea is to narrow down the estimate distribution. This idea looks tempting. We can try to reduce or control all possible factors that affect estimate distribution, thus increasing estimates accuracy.
Credit: Ayssa Gregory, Federico Belloli, Michael Dubakov