Start with proven experience, not the size of the portfolio. Ask to see two or three case studies that match your stack, and then find out who actually wrote that code. A serious vendor will put you on a call with the tech lead. Answers that name nobody at this stage usually mean you are talking to a reseller.

The agreement needs more scrutiny than the proposal. A few clauses carry most of the weight: flutter development agency intellectual property assignment, confidentiality, and notice periods and handover. All the work product has to transfer to you on payment, along with documentation, pipelines and deployment scripts. Watch for any clause that leaves so-called reusable libraries in the vendor's hands, since that is often exactly the piece that locks you in.

Find out how the estimate was built. A serious estimate is accompanied by the assumptions behind it, a breakdown by feature or module and an explicit range. A fixed-bid deal works only when the specification is complete; in any other case the supplier adds a risk premium and you pay for it anyway. A time-and-materials model shifts that risk to you, so it needs a cap, regular demos and transparent reporting.

The delivery process matters as much as headcount. Find out how change requests are handled, who writes the acceptance criteria and custom education software development how quality assurance works. A dedicated development team should be able to walk you through a working build an mvp every one or two weeks. Written acceptance criteria stay the only reliable protection against the it-was-never-in-scope conversation.

Last, plan for the handover while the relationship is still good. Require that the code repository sits under your account from day one, and that documentation is written as you go rather than left to the end. A provider confident in its own work accepts it without argument; hesitation here tells you most of what you need to know.