However, those houses are surrounded by people earning an average income of $22,000 a year.Location, location, location.

Here are a few initial questions that I have: - I'm wondering if there's a recommended corporate structure for these type of business activities, focused primarily on both short-term and long-term rentals.

if you talk to other investors that flip properties the majority will tell you that they have an S-Corp or LLC with S-Corp election. 

Personally, I analyze the residential units as guaranteed income and don't look at the commercial space at all.

She's not on title, she may be able to close in her name alone BUT no your income would not be included for a "first time buyer" as you own.

He's not an accredited investor so he can't deduct losses on personal income. 

When qualifying in this regard, since this is considered variable income, you will need at least 12-24 months of receiving this form of income, in order to use it for qualifications, similar to travel nurses.

I just don't really recommend selling a property that you're doing well with in terms of rental income and appreciation. 

I have almost no capital to start, but have a steady income from my day job.

House hacking right now in many areas will be at a loss, but less of a loss than owning something with no income coming in on it.