What actually drives custom software cost and how to scope a project without guessing.
There is no honest one-number answer
Custom software cost depends on the workflow, users, integrations, data, security, reporting, mobile requirements, and how much of the process needs to be automated. A small internal workflow tool and a multi-company platform are not the same project.
Scope is the biggest driver
A focused tool that solves one painful workflow can often deliver more value than trying to build the company's entire operating system in version one. The fastest way to control cost is to identify the smallest useful product: the few screens, rules, and reports that remove the biggest friction.
Complexity hides in rules and exceptions
The number of pages is rarely the hard part. The real work often lives in permissions, approvals, calculations, file handling, integrations, exception logic, historical data, and the rules that make the system trustworthy.
Build in stages
A good project can start with one workflow, prove the value, and expand. That creates a cleaner feedback loop and keeps the business from paying to perfect features before real users have tested them.
If this sounds like the workflow your team is fighting, document where the information starts, where it gets entered again, and what the final deliverable should look like. That is enough to start scoping a better system.