Generally, in a community property state ( Arizona included), the debts of the married non purchasing spouse may have to be included for mortgage qualification. There are complex rules that may allow an exemption based on when ( and what state) the prior marriage was dissolved but they are very limited in scope. Also,if the non-purchasing spouse has co-mingled or joint bank accounts with the purchasing spouse that clearly show the child support is paid through one of the joint accounts,the child support most likely will be considered by the underwriter in the overall debt ratios of the purchasing spouse. If you provided these joint bank statements showing the child support payments were/are paid from the co-mingled/joint bank accounts, the underwriter will very probably require the debt to be included. To offset this, consider having the non-purchasing spouse become a co-borrower if he/she has qualified income and/or assets and acceptable credit.