A range, not a day rate
A day rate is a price for the supplier's time, which is the one thing a client cannot judge the value of. Two studios can quote the same day and deliver four weeks apart, and neither quote tells you which one you are buying.
So we quote a range: what the first phase costs, what the whole thing costs if nothing surprising happens, and the single thing that would move it. You can decide from the range, and we can be held to it, which is the point.
What the number includes
Everything that is not a third party's bill: the thinking, the design, the build, the testing, the launch, and the first month of us answering questions about it. Hosting, domains, stock photography and type licences are named separately because they are somebody else's invoice, and pretending they were ours would make the total look smaller and then arrive anyway.
What it does not include is a second design direction after the first one has been built. Changing your mind is fine and normally cheap; changing it after we have built the thing is a new project, and we say so at the start rather than in month two.
Why we say all of it in writing
Because the alternative is a client deciding what "some small tweaks" means after the invoice. A proposal with the scope, the range, the assumptions and the exclusions in it is boring to read and it is what keeps a project friendly: nobody has to argue about what was agreed, because it is on the page.