Because it often has an interest rate of 15% + and every dollar you put into that is essentially a guaranteed 15%+ return.

@Aaron R.USDA guaranteed and direct loan programs are for single family properties only (including houses, approved condos, new mobile homes, townhouses). 

I'm not sure what to say in regards to my down payment since I am the one guaranteeing the note.

Leasing the buildings is a way to get you to manage the property, get around the real estate law and avoid a guaranteed commission for managing. 

Paying off a mortgage is a solid guaranteed investment at an interest rate higher than you can get from any AA investment (like a bond).One endorsement of 15-year loans is on BP podcast #279 starting at 5:10 and continuing for 

They also have a money back guarantee.

He also is guaranteeing payment from tenant even if he gets a loan through air force then have it come out his check.

I learned something new the 60th deal, and I guarantee I'll learn something new on the 6,000th deal.

I do have to point out I am weary about buying systems and I typically don't invest with those I do not trust, or ones that at least don't have a money back guarantee.

If they are worried about a rent raise write in a guarantee 12-18-24-36 month no rent raise guarantee.