First, I am aware that there are already several posts about self-funding a PhD. I'm posting this question, however, for the following reasons:
Many threads are mostly about US schools, whereas the PhD I'm considering is in the UK.
Also it is sometimes unclear what exactly counts as 'self-funding' - if I can teach to earn some income, am I still self-funded? Again, I understand that in North America, normally an offer of admittance includes a TA contract in some form, while this is not the case in the UK. So an unfunded offer in the US might look quite different from in the UK. Also, I do have funding to pay the full tuition fees and teaching is available, so at least I won't go into debts.
Many questions are about PhDs in science and engineering, while my field is in social sciences/humanities.
A lot of questions were about how a self-funded PhD is perceived both by funded peers and after completion in the job market. This however is not my main concern.
I have to decide between a job offer and a PhD, rather than between two different PhDs one funded and another unfunded, for example.
I am not wealthy, but I can manage by combining teaching with family support for the next 3-4 years. The average income from teaching for TAs in the UK was about £400 per month in 2012, so while it might be slightly more than that now, it's certainly not great. It's just enough to survive on (combined with family help). The university I was accepted at is a non-Oxbridge Russell group university. My potential supervisor has been very happy to help me with scholarship applications and answer my questions. Also the fit in terms of research interests is great.
I also have a decent job offer in the public sector in the UK. I could take the offer and quit in October to start the PhD, but I'd rather not do that because it'd be somewhat unethical to take the offer knowing that I'll quit in a few months. The job itself is unrelated to my academic interests, nor is there any way I can come back to academia through this job. Of course, I could stay in this job and reapply for full-funding although there is no guarantee that I'll get any funding at all, even the tuition waiver I have, next time. In any case, if I accepted this job offer, it wouldn't be because I am enthusiastic about the job itself; it'd simply be so I can make a living until I can do a PhD. My career goals might change and new opportunities might arise, but for now I am set on staying, or at least trying to stay, in academia.
What advice would you give to someone in my situation? What I tell myself is that I'm relatively young (early 20s), so investing in my goals at this point in my life is not terribly foolish. I would have felt a bit differently if I was, say, 30. But I do feel a little foolish to turn down the job offer. After all, a year of work experience can't be that bad even though the work itself is not terribly interesting. Should I take it, turn down the funding offer, and reapply?
Edit: My question is: Assuming that my goal is to stay in academia, should I take the partial funding offer and do the PhD this year, or decline this funding, take the job offer, and reapply until I get full funding?