The "plan for roughly double" point is the one most budgets miss. I would add a fifth question to your list: what does a usable ad cost after the edit, not just after the render? Captions, sound, a pass to fix the first two seconds and a compliance check on claims take real time, and that time is usually where the per-ad cost actually lives. A simple way to budget: track renders kept versus renders made for one week, multiply your per-render cost by that ratio, then add your editing minutes at your own hourly rate. That number is far more honest than any headline price, and it makes comparing workflows (not just tools) much easier.