3 units...1 uninhabitable, 1 unknown tenant, 1 squatter

[Pat Jackson]

I'm considering buying a "triplex" (its really a duplex and a SFR on the same lot" It's in a C+ neighborhood. Fixed up it would cash flow very well. It's located in Missouri, and is an REO. It's on the MLS

My realtor (I live in Nevada, so this is long distance) went by, the downstairs unit has a tenant that claims to have been paying rent to the owner, unassumingly to whoever lost the house. The upstairs unit has been gutted and isn't inhabitable, and the SFR out back has squatters.

I'm likely just going to run away from this deal. However I'm curious how easy it is to evict people in Missouri.  I'm mainly interested in the situation with the owner losing the house and the tenant who claims to have been paying rent.  If that's actually the case, what rights do they have?  

Anyone think this tunnel could have light at the end, or just run away?