Draw the line early
Write down who owns each layer: design, build, content, deployment, maintenance. Ambiguity here shows up later as two half-finished halves.
Shared conventions
If your team will maintain the output, we adopt your naming, structure and stack conventions rather than imposing ours.
Review points
Your engineers or designers should see the work at phase boundaries, not only at the end. Late review is expensive review.
Handover
Handover is a scheduled session plus written documentation, not a zip file dropped at midnight.