Extention DL (Bad News) you haVE to pay £649 or £1500

[ethank01]

Hi.

I'm a British citizen born in Malaysia but i've been British since i was 6 years old when i was adopted by my uncle and auntie, making me British.

July 23rd 2012 i got married to a Filipina, and we got an IDLR through discretionary terms due to our disabled daughter and the fact that i didnt meet the 18.6K earnings that came into force on 9th July 2012.
Her residence permit runs out on 14th December 2016. I was told we are to fill out a FLR(DL). But i am wondering if we are able to meet the terms or not. Is there a page with the requirements and such.
I work full time at Stansted Airport, but I am also in receipt of Child Benefits, Child Tax Credits, Disability Living Allowance, Carers Allowance, Working Tax Credits. And the wife is working part time under £100 a week due to the carers allowance terms.

Please can someone help?
thanks
E