As big and reputable as they are, I figured I could trust them to handle tenant screening and management but, I suppose, a bad apple can get past even the most stringent screening.  

Hi @Christopher GriffinWelcome to the BP community.There is a wealth of information here.I would suggest that you join a local REIA group.You can meet a lot of investors that can give you some tips.I also suggest seeking some legal advise from a reputable real estate attorney.  

While I build a reputation for rehabbing I intend on acquiring a few investors to expand my rehab projects even further.  

Have the work inspected by a reputable licenced general contractor or Home Inspector ASAP.

I know a couple of reputable builders NYC.I can refer you to them if you like they can inspect the work that was done, let you know what you estimated cost to complete will be.  

For an individual with limited capital, experience and reputation to be able to "tie up" one of these notes at a low enough price to be able to find a buyer at a higher price would take so many offers and hours that the return would be about the same a for a multi level marketing program, I.e. something south of minmium hourly wage.  

Make sure when you are trying to find renters that you set up a screening process, a high quality tenant means timely payments, better upkeep of property, longer term which equals less turnover.If you are looking out of state make sure you find a reputable and licensed property manager with boots on the ground.

Additionally, I would like to improve the block by somehow purchasing properties near the school, rehabbing them, and filling them with reputable family-oriented tenants that would serve as a deterrent to any possible gang activity in the future.

Have a potential HUD property in Lancaster SC and would like to find a reputable contractor to help me evaluate the repair value of the house. 

I can't afford to just go to the most reputable/priciest guys yet.