I would suggest following these steps:
1-Use Bigger Pockets Calculator to run the numbers.
2-Vet several contractors and have them give you quotes on things that need to be done to get it market rent value
3-Ask to review leases. If there aren't any or most are month-to-month, red flag but not necessarily a deal killer. Your first order of business is to establish uniform application, credit and criminal background check on everyone there.
4-Request rent payment history for the past 1-2 years. If the current owner doesn't have records to show you, red flag but not necessarily a deal killer.
5-If there are no washer/dryers in the apartments on onsite, you can create a laundry space where you partner and lease with a company providing this service. It's an additional source of income. If you install new washes/dryers in each unit where there are none that builds your case for rent increase.
6. Check with your insurance agent, make sure you buy in an entity or trust.
7. If you're buying $130K cash then great. The last thing you need is an underlying mortgage with rehab costs rolled into it and supporting a family of 6 on your own.
If you have more questions let me know. I'll PM to give you an idea on the type financing you could qualify for rehab.