That way, you'll know exactly what they are looking for, how they evaluate deals, etc.  3) Lastly, do some respectable marketing.

The inherited tenants learned this immediately and it strike a respectful fear that complaining about "not having the nicest" may backfire.

You will only attract the worst penny pinching buyers out there who will never respect you or your time.

If the latter, how is this typically handled with respect to escrow?

Amar with all due respect, I’m not sure if you quite understand how you are representing yourself as a professional RE agent in a professional environment.

Specific repair projects and supplies, maintenance that are property specific are listed on the Schedule E for each respective property.

Additionally I would also suggest you identify your metrics i.e. cash flow/appreciation/class of property/landlord tenant laws in the respective state and any other metric that propels you toward a specific goal. 

I am thinking the easiest way would be promissory note, but I was curious if there was any way that I could secure their respective liens on the property.

Look into setting up an LLC with each of you having your respective percentages.

If you treat people with respect and show you actually care about them, and their well being, they will reflect that back to you.