Under some circumstances you can buy right away. It depends on 'extenuating circumstances'. I am working with my mortgage partner at the moment to find out how the underwriters define 'extenuating circumstances.' With your credit score, if you can manage the payments until the home sells you may be able to buy again right away. If you will contact me here on Trulia I will do my best to provide you with the definition and circumstances once I learn what, exactly, they are.