The fact that you are not able to work on the dissertation is not enough, to hire someone who is not qualified to handle your paper. Many rookies claim to be writing agencies, but do not have the writing resume to support the claim. That is why it is normal to do a preliminary investigation on the likely firm that you are about to contract the writing assignment to.
Indecision on how to go about the writing and the research
The dissertation may be somewhat tricky, or the idea may not be clear on how best to go about the writing. Since this is not a job to use as an experiment, it is better to consult professionals who have a proper understanding of the field.
The right way to approach the dissertation writing may be the first problem to face. This is common to many students, so you are not alone in this, but there is no need to waste precious time, brainstorming on how to start; get help from professionals who are willing to help you out with the writing.
Even the research aspect could be a problem, reading, gathering journals, visiting the library and surfing the internet may not be okay for you. If you are not sure of how best to go about your dissertation tips, you are not alone in the shoes, therefore, seek help when there is time to do so.