I actually helped a fellow realtor finance a STR in Johnson city and she seems to be doing very well.

I do get nervous with finances and want to be financially responsible.

I intend to rent out the units by room to college students (does it sound like this would work in this area and what are some general tips/things I should look out for?).

Just a tip - make sure you don't just look at the current property taxes. 

Consulting a tax professional now can help structure ownership and financing efficiently, ensuring you take full advantage of deductions, depreciation, and potential tax-saving strategies like 1031 exchanges in the future.This post does not create a CPA-Client relationship.

You also mentioned you started pretty young, I am 18 and just purchased my first college rental, any tips? 

Your credit score will be worth improving to acquire better financing options.

Quote from @Daniel Tanasa: Another option is to get a small cash out refinance from the house you plan on fixing up, if is in financeable condition, and use that to fix it up, while still cash flowing.

What would be my best route to take if we need additional finances?

And could even get a second home loan if doing traditional financing.