I am new to the LLC side of things, but currently have two houses and a duplex, so I would like to create a relationship for future problems that may involve a lawyer.

This involves calling the PM for the HOA who called the tenants, and when it continued, call the out of state owner, who couldn't be located.

There are significant liability issue involved with tenants installing their own units.

RCW 9A.52.090    (Revised Code of Washington)Criminal trespass—Defenses.In any prosecution under RCW 9A.52.070 and 9A.52.080, it is a defense that:(1) A building involved in an offense under RCW 9A.52.070 was abandoned; or(2) The premises were at the time open to members of the public An owner may, through words or actions, express or imply that he/she no longer has interest in the property. 

Probably not, but you should read the actual not involved. 

What other parties do I need to get involved in this?  

@Aaron WintersI would consider the costs and process this might involve with whatever town/county/city you are buying the property in.  

What would be some things I should really be aware of if I did want to get involved in this property?

There are two aspects to analyzing and buy and hold deal in my humble opinion, and especially a deal involving Multi Family Units. a) The Property Condition and Rehab required:  This is something you should be able to, and probably should do independently. 

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