I do not understand where liability is from a servicer for enforcing the terms of the documents, which typically includes obtaining proof of insurance yearly.  

See Mindy Henderson for a referral.Here is a map showing in what states I can operate.http://mortgage.nationwidelicensingsystem.org/profreq/testing/Documents/UST%20Adoption%20Table%20and%20Map.pdfThe rest of the states require a LO to be approved by their state commission individually.

And always do transfers through an escrow agent in the US (or Canada or Europe for that matter, depending on where you are based): never ever release any money, unless all documents, title, property clearing is in place.

From reading and some experience looks like the lender will require a package from me (buyer and seller) requesting different documents.

I love short sales I'm a CD PE expert also I got my certification for short sales and they are not as hard as people make them to be you just need to create your system I use a lot of computer base for my forms and I email them to my clients and have those filled out by the time I get there I have them have all the documents that I need from them ready when I get there to their house and you usually get both sides of the check for closing, not hard to do.

The family contact doesn't remember where the trust document is located anymore. 

Our purchase contracts are part of this body of documents.

What kind of legal documents should i have available (cfo, anything else ) ?

Be prepared to deal with L+I, inspections, setting up a business and paying BPT.Most people who are looking to have rentals in Philly don't understand the importane of the License.https://business.phila.gov/Documents/Licenses/part...

There are more documents needed than just a PSA.