mortgage with defaults

Hi,

I am looking for a mortgage however struggling, I work f/t with the same company for 12 years earning £22000 pa.

I have had bad credit in the past of small amounts that are £415 default 4/9/09, £549 default 5/11/10, £420 default 4/1/08 and £571 default 26/5/11.

Can someone please advise me as when i seen a mortagage broker they gave a possible offer if i had a 25% deposit, I can stretch to 15%. Can someone please advise me further I am looking to buy the property i currently rent privately, £115000 is the house price.

Please help

Thanks :(:(