Squatter in Los Angeles property

[Rob Duke]

So I have a condo I am considering buying and flipping.  I went to inspect it and found a guy living in there. Trash everywhere inside there and I don't think the electricity was on. I started talking to the guy and I asked who he was paying rent to and his story changed 3 times, First the 'owner' who he then said died 2 years ago, then the HoA(condo) and then the property management company which he could not tell me the name of. So I am not sure whether he is a Trespasser(broke in via unlocked window) or Squatter.

What is the best way to proceed if I should buy the property?