In web system development, the initial estimate and the final amount can vary significantly. Much of this is due to the fact that it is often not determined at the initial stage rather than the development cost itself.
For example, do you need a login feature? How many types of user permissions do you have? (It's surprisingly easy to get out of here.) Do I need a management screen? Do I need email or chat notifications? Is there a payment function? Do I need to support smartphones? Is there cooperation with external systems?
If you provide a vague estimate for these items, it will be easier for additional work to occur as development progresses.
In addition to the number of screens and functions, the complexity of business rules also affects the amount of money.
Even with the same reservation system, whether you simply choose the date and time, manage the availability of each agent, or include cancellation fees and payments, the content of the development will change greatly.
You don't need to create a perfect specification first to reduce the skew in your estimates. However, it's important to organize the purpose of what you want to create, who uses it, what features you need, and what your priorities are.
In Makoto Tejima, you can consult even at the stage where the content is not solidified. You can also check the general cost sense in the approximate estimation simulator and organize the formal contents.
