Hi!
I don't know whether this is any help to you but I had a very similar situation when askd to care for a full time 3 year old back in september. I explained everything at the interview and explained that I normally charge a month in advance but in her situation I was happy to only do a week in advance ( and get paid every Monday). The mum spoke to her Lone Parent advisor at the job centre ( who was getting a big bonus for getting this parent back to work) and the Job Centre eventaully paid the 1st weeks money for her. This did take a lot of input from my part, I had to fax an invoice and copies of the contract to the job centre but within an hour of the meeting the mum was at my door with the 1st weeks money in cash. The second week, the mums tax credits were in her bank by the Tuesday so I got paid 1 day later than the contract stated, and then we changed payment date to Tuesday mornings instead of Monday as she gets her tax credits weekly. basically she pays me cash as soon as the money goes into her account every week. So far, no problems at all, the mum is totally reliable with the money, better than most of the other mums who probably are more able to afford the fees. It may be worth ringing your mindees mum and asking her to ask at the job centre for the 1st weeks fees to be paid. Then if she rings the Tax Credit people on her first day at work, there is no reason why her tax credits won't be sorted by the following week. Hope this helps, and Good Luck! Karen