In practicality it attached to all real estate owned in that county, but the plantiff can refile the judgement in multiple counties where the defendant owns real estate. 

I picked RE because I had a lot of practical knowledge and experience that I thought I could leverage to add value to my purchases.

I want to live in one bedroom and fill the other two bedrooms with “Tenants” / old college friends that have agreed to pay rent if I purchased the house.

At least that's the practical approach.  

You have a de minimis exception which is set at $2,500, and it can be doubled to $5,000 if you follow certain strict and tedious accounting practices known as AFS.

As you can imagine, we already have an attorney who specializes in real estate and an accountant who is well-versed in rental property accounting best practices (but she admits she doesn't have a lot of experience on the private lending side of the business). 

This is just for practice for now so the most important thing is just looking at the numbers to gain an understanding, don't put too much pressure on it at this point, it's a muscle you have to build by doing reps. 2.

I am targeting college students.

I would educate the tenants on why certain practices of the unit might cause it to break.

I think if the market makes sense, you can also try mid term rentals or college student housing.