Look first at domain experience, not the number of logos on the website. Ask for two or three engagements that resemble your domain and igaming software developers your stack, and then ask who actually wrote that code. A solid partner is happy to connect you with the tech lead. Vague answers at this stage generally mean the delivery team is not the team you were shown.
The paperwork needs more scrutiny than the proposal. Three clauses do most of the work: ownership of the code, confidentiality, and exit terms and handover. All the work product must transfer to you on payment, together with designs, scripts and infrastructure configuration. Watch for language that leaves framework code with the vendor, since this is frequently exactly the piece that locks you in.
Ask where their numbers come from. An honest estimate arrives with a list of assumptions, a breakdown by feature or custom real estate software development module and a best case and a worst case. A fixed price only makes sense when the scope is genuinely frozen; otherwise the provider adds a risk premium and you pay for uncertainty either way. Hourly billing shifts that risk to you, so it needs a cap, regular demos and transparent reporting.
How the work is run matters more than team size. Ask what happens when the scope changes, ai chatbot development company who writes the acceptance criteria and how quality assurance works. A well-run team should be able to show you a working build every one or two weeks. Acceptance criteria in writing stay the practical protection against an argument at delivery time.
Before signing, plan for the end of the engagement at the start rather than at the end. Require that the repository stays under your account from the beginning, and that a readme and architecture notes are kept current as the code changes. A vendor with nothing to hide will agree quickly; resistance at this point reveals most of what you need to know.