In your neighborhood, you don't want to have a vacancy very long, because things can tend to 'go missing'.If one tenant has sufficient income to qualify based on your standards, but the (probably) student with no social (BTW, get a copy of their visa for your records, and proof they are a full-time student) does NOT have provable income or background, the ONLY way to go is to get first, last and security.Since you are living there, you will have a better handle on the day-to-day, and you MUST stay on top of things. 

For the later you need to judge if the space is sufficient and this would work for you.

- If we buy a couple thousand acres of ranch land, but it is only used for grazing in the summer, is that sufficient?

They hear the words private placement, see fancy offering materials, and watch rousing deal webinars and they get that excited (premature) bowel movement feeling.The financial protections (net worth and/or income) from the high risks of private placements are important and just having the knowledge part may not be sufficient protection. 

Honestly, I think your best bet would be to really focus on your credit for now until you can get it to a level that is sufficient to do a HELOC or a home purchase.

For a while, I was trying to start a business of running vacation rental properties but ran into financing issues as I had an extremely hard time trying to get sufficient capital to expand quickly. 

You just might have  sufficient funds to close? 

Generally i try and stay away from contracts and deal with straight purchases but given the condition of the house i do not have sufficient funding to buy the house outright.

I feel it is a great deal and I don't want to get beat out on my first deal because I didn't have a cash offer.If a HML requires a renovation, then would a new roof and AC added be sufficient to allow for the loan to go through? 

This requires a bit more planning to make sure you never term out of your commercial mortgage during a period of time when values are not favorable for a refinance like at the bottom of a market cycle.So with sufficient foresight and use of the pro's while minimizing the con's I side with commercial financing from a RE investor perspective, but for the newer aspiring investors I will side with conventional since its financing with training wheels that favor the borrower.