Two quotes for “the same app” can differ by a factor of ten. Usually the vendors are pricing different projects, because the scope was never written down. These are the factors that drive price, roughly in order of influence.
1. Scope and number of features
Every screen, user role and rule adds design, build and testing time. The fastest way to control cost is a clear first version with only must-have features.
2. Integrations
Connecting to payment providers, CRMs, ERPs or older internal systems often takes longer than building new screens, especially when the other system has limited documentation.
3. Design detail
A clean interface built from a component library costs less than fully custom illustration and animation. Both are valid; choose deliberately.
4. Data migration
Moving and cleaning existing data is frequently underestimated. Ask for it to be quoted separately.
5. Compliance and accessibility
Privacy rules, audit logs or WCAG accessibility add work, but are much cheaper to include from the start than to retrofit.
6. Timeline pressure
A hard deadline can require a larger team working in parallel, which adds coordination cost.
How to get a reliable number
Write a short brief (see our guide), ask for a fixed quote for the first version, and keep future features on a separate list. Our custom software development team starts every project with a written scope and a fixed quote. Starting prices are on our pricing page.