This would be an October rental, so probably not a student rental? 

Like you I had no student debt.

If you're self-employed, the Solo 401k will likely be the better fit for you.Here are few Solo 401k benefits:Compared to an IRA, Solo 401k contributions limits are roughly ten times higher.There is no custodial requirement for the 401k.You can take participant loans from the plan.You don't need the additional expense and administration of an LLC to have checkbook control.There is a built in-Roth component whereas IRAs are either traditional or Roth, not both.A spouse can also participate in the same Solo 401k plan.The Solo 401k has additional tax benefits over an IRA when investing into real estate using leverage.If you're not self-employed or if you have a business with employees, the self-directed IRA will be your main option.

Currently I am 22 years old and recently graduated with my business degree and luckily no student debt.

Poor choices 5 years ago and nothing negative since, defaulted student loans, or current unpaid credit cards and utilities.

The neighborhood I was interested in is a college-town, so many rentals are occupied by students, as landlords can make more money charging students by the room as opposed to renting to families. 

Student housing is a good option for boardng space.

Does the general partner (sponsor) generally participate in that?

Not a very common strategy out here, even in the student rental space in Tempe around ASU.

,I am currently a university student working as an undergraduate engineer living in Queensland, Australia.