Missing Landlord! Austin, Texas

[Santos Gloria]

I wasn't sure what part of the forum to post this in but here it goes. I recently ran into a few townhouses in Austin, Tx, where it appears the landlord has gone missing. From what I have gathered, he is an accidental landlord, who took over the properties when his mother was unable to continue managing them. According to a long term tenant (3yrs.) when the son took over management, the quality of service dropped, and he was very hard to get a hold of. Repairs where done very slowly, and for the past couple of months all of the tenants rent payments have not been claimed and are being returned to them. As a newbie to real estate, I'm not sure what my next step should be. How could I find out if the properties are paid off or if the payments have not been made? Any help would be appreciated. Thank you.