The affordable housing programs in my area have the same limitations... they are under market value for the types of homes (tend to be townhomes or condos), you can either take the city held 2nd mortgage (which usually doesn't have payments) or just qualify for the full financing on your own. Either way though, they have restrictions on how much you can sell the home for, and if you take the city held 2nd mortgage, it will get to "share" in any equity the property has gained. If you are unable to afford anything else, and you really want to own a home, it is a good opportunity.
To determine if the tax break would be significant, you would have to be able to write off more than what you are currently taking for your standard deduction (which should be $10k). My guess is that the interest & property taxes you'd pay each year would be more than $10k, so it would be beneficial for you that way.. however I am not a tax adviser and I don't play one on TV, so I would recommend you speak to your own tax professional regarding how interest & property tax deductions would benefit your exact situation.
If you make ~$3k/mo I don't see how you would get pre-qualified for a condo of approximately $370k. Something sounds very fishy there. However being prequalified doesn't amount to a hill of beans, you really want to get pre-approved. We pre-approve by taking a full loan application over the phone, sending you out the loan application & disclosures, providing you a document checklist for the items that would be needed for an underwriter to review, ask you to sign/date the loan application & disclosures, and send those back with all of the items on the document checklist. Then we submit the loan through automated underwriting for an immediate response, and if needed, we send the loan into the underwriter for a full review. Once the underwriter gets back to us with an official pre-approval, that means you've been officially pre-approved.
Doesn't really sound like you've been talking to the right people... this is evidenced by you having so many questions after talking to them. Don't get me wrong, asking questions here is perfectly fine (actually I get concerned when clients don't ask questions, makes me feel they aren't getting the "big picture"), but it sounds like you've been talking more to salesmen & saleswoman than to mortgage professionals, as if you discuss your situation with the right person, you should leave the conversation having all of your questions answered, and then some.
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