A quote that comes back within a day counts as a red flag rather than good service. An experienced provider will come back with questions first: next.js development agency about who owns the data and what happens on failure. A supplier that commits to a figure without asking anything is probably guessing, and that guess becomes a change request later — on your budget.
Be wary of a mismatch between the team in the pitch and those who eventually appear in the repository. Insist on the names and CVs of the actual team in the statement of work, with a clause covering replacement. A provider that will only describe roles and will not commit to specific engineers is reserving the right to assign anyone it likes.
Insist on access to the repository from the start. A partner that hands over a build only at the end of each phase is asking you to trust a black box. Visible commits tell you how many people are really working far better than any status report. This extends to the automated test suite: if nothing runs automatically, promises about quality are just talk.
Vague phrasing around IP is rarely an oversight. The contract should state explicitly that the code, designs and documentation transfer to the client as they are paid for. Check also the jurisdiction and how payments are structured: a large upfront payment with no milestone tied to it removes the only leverage you have.
Finally, look at the working rhythm. Establish what overlap there will be with your timezone, which named person answers questions and within what time. A few hours of overlap generally works; no overlap stretches every clarification into a twenty-four hour round trip. Unclear written communication hire developers in dubai the early emails rarely improves once the work starts.