It is probably one of those occasions when it is better to go through a broker. Unfortunately you may find that with a bad credit rating you will pay a higher rate of interest than others. If you have a close relative who would guarantee your loan you may be able to borrow from a High Street lender at normal rates
You may be able to improve your chances of getting a decent rate mortgate by ordering your credit report from the main credit reference agencies (www.equifax.co.uk and www.experian.co.uk) and making sure everything is up to date. For instance, you might have to get a certificate from the court to make sure a previous CCJ is shown as paid. You can also explain the reasons for past difficulties on your credit report and this may help you. Gpod luck!