I really don't know why agents answer these questions becayse none of the information you have received so far is accurate. The people telling you 3 years have obviously never read the Fannie Mae selling guide or they would know, as you obviously already do, that 10% down financing is available after 2 years with extenuating circumstances. (20% down without)
As for what constitutes extenuating circumstances, the selling guide addresses that too.
From The selling guide:
B3-5.3-08, Extenuating Circumstances for Derogatory Credit
"Extenuating circumstances are nonrecurring events that are beyond the borrowerâ€™s control that
result in a sudden, significant, and prolonged reduction in income or a catastrophic increase in
If a borrower claims that derogatory information is the result of extenuating circumstances, the
lender must substantiate the borrowerâ€™s claim. Examples of documentation that can be used to
support extenuating circumstances include documents that confirm the event (such as a copy
of a divorce decree, medical reports or bills, notice of job layoff, job severance papers, etc.)
and documents that illustrate factors that contributed to the borrowerâ€™s inability to resolve the
problems that resulted from the event (such as a copy of insurance papers or claim settlements,
property listing agreements, lease agreements, tax returns (covering the periods prior to, during,
and after a loss of employment), etc.).
The lender must obtain a letter from the borrower explaining the relevance of the documentation.
The letter must support the claims of extenuating circumstances, confirm the nature of the
event that led to the bankruptcy or foreclosure-related action, and illustrate the borrower had no
reasonable options other than to default on their financial obligations."
Assuming you have restored your credit and not incurred any other derogatory events, Fannie May DU could potentially give the approve/eligible which would be required. If you get that finding from the automated underwriting and you have sufficient documentation of the reasons for your short sale then it's certainly possible.
If you would like assistance, I would be happy to help you with your approval.