A number produced without questions counts as a bad sign. Any serious hire dedicated team will come back with clarifying questions before any number: about integrations. A vendor that quotes without asking anything is simply pricing a guess, and a guess will be corrected later — and you will pay for it.

Look out for a mismatch between the engineers on the sales call and the developers actually assigned. Ask for the names and CVs of the actual team in the agreement, with a clause that requires notice before anyone is swapped. A provider that only offers roles and will not commit to specific engineers is preserving the option to staff you with whoever is free.

Ask for access to the repository from day one. A partner that hands over code only at milestones is inviting you to take delivery on faith. Regular commits and pull requests show you who is really on the project far better than a slide deck. The same holds for the CI pipeline: if it does not exist, assurances about quality remain just talk.

Loose wording in the contract around IP is rarely an accident. The contract must state explicitly that all outputs produced under it become the property of your business on payment. Look too at the governing law and the milestone terms: heavy prepayment with nothing due in return for weeks takes away the only leverage you have.

Lastly, look at communication. Ask what overlap the teams will share each day, who handles questions and within what time and materials vs fixed price contract. A few hours of overlap generally works; zero overlap turns each small question into a day of delay. Sloppy written English in the sales phase rarely improves later.