Thank you for your question, and thanks for using JustAnswer.com -
1. This is a legal question which requires review of law, and I am not an attorney. The best way to get your brother's income counted would be for him to be a purchaser of the house as well, so he would own the house along with your wife.
2. Typically a lender wants to see 1-2 years of stable employment history. This depends on your lender and is something you would discuss with them.
3. This shouldn't pose a problem, because your wife was not responsible for the loan.
4. No, your income cannot be counted in the loan as you will not be party to the loan document.
Thanks again for your follow ups, and please let me know if I can be of any additional assistance to you in this matter. Thanks again for using JustAnswer.com and have a happy, and safe, 2013 and good luck with your new loan!
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You should be aware that your question, as with most tax questions, can never really be answered completely...addressing all the permutations; that is because of the many assumptions that have to be made I have done my best to determine what I think you are asking and answering it in the most direct and understandable manner possible. If, however, after reviewing the questions, you have any uncertainties or further questions, please do not hesitate to ask.