Look first at relevant experience, not the number of logos on the website. Request two laravel or django three projects that match your technology stack, and then find out who actually wrote that code. A serious vendor will put you on a call with the people who would work on your project. Vague answers at this stage usually mean the demo work came from somewhere else.
The paperwork deserves more scrutiny than the proposal. A few clauses carry most of the weight: assignment of intellectual property, confidentiality, and exit terms and handover. Every artifact should transfer to you on payment, including documentation, pipelines and deployment scripts. Be careful with any clause that keeps so-called reusable libraries outside the transfer, because this is frequently the dependency that makes switching painful.
Ask how they estimate. A serious estimate arrives with a list of assumptions, a breakdown per feature and an explicit range. A fixed price only makes sense when the scope is genuinely frozen; otherwise the provider adds a risk premium and you pay for it anyway. Hourly billing shifts that risk to you, so it demands a cap, regular demos fintech and crypto software development company transparent reporting.
The delivery process matters as much as the number of developers. Establish what happens when the scope changes, who signs off on a feature and how quality assurance works. A well-run team should be able to walk you through a live build at the end of each sprint. Acceptance criteria in writing remain the practical protection against endless rounds of rework.
Before signing, consider the day you no longer need this vendor before it becomes urgent. Require that the code repository stays on infrastructure you own from the beginning, and that the documentation is refreshed in every sprint. A provider confident in its own work says yes immediately; a long negotiation over it tells you a great deal.
