I'm trying to buy my first place through the share to buy scheme. I've got a reasonable deposit and enough for all the legal fees, but because of my bipolar I defaulted on a credit card a few years ago. 
It's all been paid off now and I've kept everything up to date since then.
It seems to have knocked my credit rating down to 630 or so, and I'm really worried I won't be able to get a mortgage at all.
Does anyone have any experience, or advice about this?