A popular method is to include estimates as a component of a job (in the same way as internal or bought-in time) – and whilst this is perfectly valid, many agencies, in my experience, prefer to treat an estimate as a separate entity, which can then be converted to a job when the client signs an order.

As for which is “best” – there is no right or wrong answer.  It is perfectly valid to have estimates as component of jobs, particularly when a single job is stretched over a long time frame, however, obviously, not every estimate results in an order, and non-invoicable jobs will start appearing in your system.  Then there is the question as to whether it is actually a job, when the only activity is estimating.  Where estimates are handled as entities in their own right, they should be referenced in the job bag that they become when converted.

When you buy software, don’t be fooled into thinking that you have to change your business processes to fit it.  Before automating a set of tasks, the critical factor to success is making sure that the existing processes are up to scratch – the result of not doing so is having flaws in your process exaggerated.  Business should always come first, software second.