This is a business; tenants are not your friends, and, like with your kids, learn to say "No" very early on in the relationship. 

Explain that you want the relationship to be a win-win scenario.

What I wrote above does not create an attorney/client relationship between us.

The agents I have spoken to seem to be geared more towards just making a buck versus building a relationship that could go beyond this one transaction.

We don't have their new address but do have the one address they just stayed at for one month while they were supposedly waiting for their new rental and we also have the forwarding address they first gave for their parents home (their parents also resided in our rental with them and are being named in our claim as well).The total damages are high and it's a big house (almost 4k sqft & in excellent condition before the moved in).So long story, we need help on what to do about serving them with claims papers if they now live on base and we don't have their new address?

I’ve found other investors by writing them letters and building a relationship.

The agent-client relationship needs to have trust and it is difficult to build this online without social proof. 

If the property tax is not astronomical, I run a proforma using an excel spreadsheet I made to see if it looks like it will cash flow.   

It is in a good neighborhood and, looking at the exterior of the property yesterday, the roof/stucco/exterior is in excellent condition. 

I hear the stories of credit unions working wonders and I make lots of calls but I guess I haven't found that kind of relationship yet.