How can a person repair their bad credit to get a mortgage loan?

There are only way to repair bad credit due to a mortgage loan is time. All debt information related to late payments and Chapter 13 bankruptcy come off a credit report after 7 years. Chapter 7 bankruptcy (total liquidation) remains for 10 years. Not that some items associated with defaulted mortgages, such as tax liens, last forever until paid and even after paid may remain for 7+ years.