Match the team to the work
A clearly bounded implementation task may suit one specialist. A product requiring discovery, design, mobile, backend and testing may need a coordinated team. Identify who covers every responsibility and include your own management time. Missing roles can create delays even when the available developer is highly capable.
Assess continuity and access
Discuss availability, knowledge sharing and post-launch support. Keep code, designs and project accounts accessible from the beginning. Ask how another person could take over and how issues are escalated. Both freelancers and agencies should provide a clear handover and avoid making the product dependent on an undocumented individual setup.
Choose a practical first milestone
Use a focused, reviewable delivery to test communication and quality. Agree the scope, acceptance criteria and commercial terms before work begins. Compare complete responsibilities and expected outcomes, not only price. Expand the engagement when the first milestone provides evidence that the collaboration supports your product and constraints.