Bad credit means the person has defaulted from making prompt payments on the loan. A person under bad credit is not considered as worthy of credit and lenders will consider them 'risky'. Thus, they will not lend money to such people.
If such people want to take a home loan, the only option available to them is to borrow money from the sub prime bad credit lenders. These are certain private lenders who give home loans even to those who are in bad credit. Since banks and financial institutions will not lend money to them, they are forced to go to these financiers only. These people charge huge rates of interest as compared to the normal loans. If you default on such loans, this will further worsen your credit score.
The best way out of this situation is to go in for bad credit home mortgage loan. Under this, you offer your house as a security against the loan you are borrowing. If you default on the loan, your house will be sold and the amount realized. Thus, this loan absolutely nullifies the risk for the lender. The lender can be without any worries and since his risk is less, the rate of interest he charges should also be reduced.
Also, even banks and other financial institutions will be ready to give bad credit home mortgage loans. So, you can shop around and get quotes from various lenders. You can ask for better rates and demand better terms. Be careful and read the fine print of the agreement before you sign any dotted lines. There may be some extra charges hidden in the document. Also, never hesitate to raise any queries you have. It is the duty of the lender to explain things clearly to you.