By "bring the loan current" he means that you'd need to pay the back payments, so if she hasn't paid 3 months that's 3x whatever her payment is.
There aren't really enough details to say if this is a good investment or not, I have a hunch it's probably not. You say the house is worth 120k market and you'd rent for a total of 1300/mo, ok, fine. But:
How much does your aunt owe on the house?
How much will you offer for it? The bank will probably not let her sell for less than she owes and if she could seek it for more she presumably would not have abandoned it.
Do you need a property manager?
Have money for a down payment? Can you get a loan?