Just a side note on doing estimates. Everything takes longer than you expect it to. Unless you've done this exact thing before and timed it, you should bump your time estimates by 50%. I'd bet money that you'll be closer using 150% of the time you think it will take than you would be with your original estimate. From my point of view, it's better to come in under budget and give the client a break on the final invoice, than to end up working many hours for little pay.
I do a lot of commercial work, and I bid it based on my pessimistic estimate. When the client asks me for revisions, I look at the actual hours, vs. the estimate and figure out if I need to charge the client extra. If I have hours that I have not burned, I'll tell the client there was enough padding in the estimate for their changes and I'll make them at no extra charge. I warn the client that any more changes will result in additional fees. Having done many jobs, I've found that my estimates generally cover the small changes the client requests after the first final draft is completed. I have to assume they will want to change something, unless I've done a lot of work for that client and I have a good understanding of what they like.
I'm rambling, but my original point is that things always take longer than I expect them to. By planning on that, nobody ends up working all night for no pay, or being upset by additional charges for simple changes.
BTW: When I first started doing commercial work, I did not estimate the time it takes to compress a draft of the final comp and put it on the internet for the client to view. I generally end up doing that 3 times for a given project. Then when it's all approved, there is the final final that gets written to tape(s) for the television stations, maybe to a DVD for the client, etc. All of these little steps take time, computer resources and sometimes physical resources.
One more thing; since clients love to drag their feet on shoots, I charge a flat $75/hour that starts when I leave my studio for remote shoots, and ends when we wrap up shooting. If the talent shows up late or spends 20 minutes in makeup while I'm waiting patiently, that's all on the bill and I make that clear up front when I do the quote. I will not quote a flat fee for shooting.
Doug