Advise needed on Tax credits.

[HaveToWearHeels]

Some advise please if I may. Sorry if this is long but I don't want to drip feed
I was made redundant back in June and my husband walked out on me and DD (6) at the beginning of September. He is currently paying the majority of the bills and I am living off my redundancy money. I used to earn 44k a year however my job was very high pressure with sales targets and some travelling. I don't feel like I can hold down such a job anymore (my current mental state is very up and down) and be a single mum. H is not a talker and at this point in time does not want to involve solicitors (although I have consulted one on the QT) and only seems to interested in my job search.
Our financial situation is complicated as we only several properties and a pre nup (which I have been told wont hold up in court as no provision has been made for DD). Our family home is large, far too big for me and DD. I however don't want half of everything and have no intention of going for half just enough for DD and I to have a little house near to her school and security for the future.
I have today been offered a temporary job at a local private school on a contract until May 2016, however the salary is 21k. My plan was to get this job, get some experience (totally different to my old job) and then try and get something else more perm in May. Obviously if I go down this route I will never earn what I was before but I will be there for DD as I may be able to get a term time only job. A friend mentioned that I may be able to claim tax credits how ever I have no experience of any benefit as I have been fortunate enough to never have to claim. When I try and use the calculator online it asks for last years salary which results in me getting £0 but if I put in 21k I could get about £300 per month.
So my questions are, any advise on tax credits ?
What would you do in my situation ?

In my experience they base it on the previous year. While in mat leave I got nothing but the following year, because I earned so little on mat leave, I got a crazy amount and help with childcare, then the following year we got nothing as I'd been back to work for a year. Not sure if there's a way round it but it's a tax year. Not sure if you'll need to include redundancy pay - sorry I'm not very helpful. I'm sure someone else will be far more helpful.

First of all I'm so sorry your dh turned out to be a shit.
However, you are not together now and the we ceases. I say this as you use we quite a bit in your OP and this can't help you move forward.
Go to solicitor, make sure you know the property and his income and let the solicitor decide what you should do.
I doubt you'll qualify for tax credits or much anyway as they keep reducing the threshold. I think it's 22k atm so you won't get much if you take a job for 21k.
They pay on last years salary so that's why you keep getting a zero.
The best thing you can do is get things moving with a solicitor irrespective of what your ex is suggesting.
He may be moving money so he doesn't have to pay as much, hence stalling you contacting solicitors.
Was their an ow involved?

On that salary you may get some tax credits now, but come April 2016, the threshold for one child will be around £20.5K I think, therefore you won't get them unless you willbe paying ot for childcare costs in which case the threshold will be higher. obviously you will get child maintainence on top of your wage. As pp says I would see a soliciter to get things sorted asap.

Just to add, I think they count any interest on savings / investments ( not sure if rental from properties counts) as income for tax credit purposes.

Thanks all. No other woman, just not happy with his life. He is currently living with his parents waiting for a property to become empty. His Mum has confirmed that he is in most evenings and when he has told me he is going out it has been with friends, whose wives I know and think he is also being a shit. Luckily he has left all the paperwork here for all the houses. He has no savings, it is all tied up in property which I know for a fact as I lent him 3k a couple of months back to pay for some repairs on a property. My friend is coming over this evening with her photocopier and we are going to go through all the files, to see how much equity in each property.
We were doing so much planning for our future, this came as such a surprise and is a complete surprise. If he had honestly though about this properly, he would have realised this wasn't the best time to leave me, which is obviously working in my favour not his.

Babyroobs I don't get any of the rental income it is all his !