A reliable independent writer will ask for at least 50% of the cost upfront, with the rest to follow before the paper is submitted to you
No legitimate writer will ever agree to write 100% of any project for only 50% paid at the time the order is placed. If the client fails to pay the remaining 50%, the writer has already wasted (50% of) his time writing the whole project, irrespective of whether or not he
submits the project to the client.
or whatever payment scheme you have agreed to
The only payment scheme to which a legitimate writer will agree is to produce and deliver __% of a project after receiving (the same) __% of the payment at the time the order is placed. Then, if the client is happy with the first __% of the project, he pays for the next __% of the project and (only then) the writer produces and delivers that next __% of the project. How much of the project is paid for and (only then) written and delivered at a time depends on whatever % of the project the client and writer agree to pay for and deliver at a time, respectively.
Typically, clients using a writer for the first time might want to pay for just a small section, first; and then, after satisfactory delivery of that section, the client pays for the rest of the project, because delivery of that section is enough for the client to know that the writer is legit. For huge projects of 50+ or 100+ pages, clients might pay for one or two sections at a time, provided that there's sufficient time to do that and still make the deadline for the completed project. However, what often happens is that by the time clients first find and reach out to a good legitimate writer, the deadline is too short to allow for sectional payment and delivery. In those situations, about the best that clients can do is research the writer on the forum and by Googling the writer and/or the writer's website and email(s) before paying for the whole project in advance. Legitimate writers don't mind sectional payment/delivery; but if clients first contact us shortly before their deadlines, there may be no other option besides trusting us with full payment in advance.