No one business is the same as another even if the product or service is similar.
If you are starting in business it is important to avoid the pitfall of underestimating your start up costs.. The calculator lists some of the more common costs; you may know of others or wish to include an estimate for those unexpected initial costs.

Markets are different, people are different, attitudes change as times change, some businesses deliver better service than others, while businesses position themselves differently. Start up costs are limited to expenditure incurred before you are ready for business on the first day. They don't include the running costs or the cost of owners' remuneration. For this the business will need to calculate the 'working capital requirement. The business should have a cash flow plan (a money map) prepared in order to identify how much working capital funding the business requires. It is a fact that customers don't always pay when they should and suppliers to new businesses press hard for prompt payment.
It is possible to make a profit and still go out of business because of lack of cash. The initial costs will be factored into your cash flow plan as will the repayment of the funding incurred in starting the business.