After looking into multiple skip tracing services and deciding on Smarter Contact, my partners and I were upset to find there were quite a few charges after paying $300 for the service; including a $140 fee to remove the "reply STOP to unsubscribe" feature.

They only get paid if they collect. 

Instead, there is an option period, with a (mostly) small option fee whereby the buyer can cancel the contract for ANY reason within the option period.  

Does the promissory note and personal guaranty go to title or should I execute these outside of escrow?

I personally have not had much of a hard time finding tenants for my apartments.

First I got preapproved (I know... another lender saying to get preapproved) of course it was important to my realtor and offer, but more important it gave me insight into what I could expect for cash needed, payments, etc. 

That is groundwork to getting the property geared up for making the most. 

I bought under a secondary mortgage (don’t have a primary mortgage but 3 hours from where I live) and I put 10% down at 6.25%.

I don't believe you can check this beforehand.

I have found myself in a place where in a recent tenant of mine is suing for personal injuries.