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5% down conventional loans are still around, at least in my area. The hard part is not getting the loan, the hard part is the private mortgage insurance companies having extremely strict standards that must be met. It's not even just the borrower (although credit score, history, etc. are all very important), it is also the type of house, location, comps, etc. Most of the PMI companies here want the perfect borrower to approve or they will walk away.
That being said, remember it will be the lowest middle score from both of you that dictates the loan, and with conventional, your credit scores do matter in your rate and your PMI approval. Good luck going forward.
I just closed a 5% down mortgage, and my financial situation in very similar to yours. If your DTI allows, try for the Fannie Mae My community Mortgage using only one person's finances, this is what we did.