Anything over £99 a month disposable income after all your bills have been paid and you will have to pay an IPA for three years. At the moment this will be between 50 and 70% of that.
Sorry to hear of your troubles and your wifes ill health.
Take good advice before BR - there may be a better course for you.
I am not qualified to advise on financial/insolvency matters, but there are experts who post here for you to tap into for nothing. They are very very good.
You may benefit from a visit to your local CAB - particularly with your wifes health - also your GP may be able to provide some counselling. Not so much for your money worries, but for the mental strain. That having been said, many GP practice counsellors have access to independent advisors.
Post here as often as you need to - there are lots of people with a wealth of experience and knowledge.