The General contractor must spend a certain amount of hours each week on each project that he is being an RMO for, and has liability for any construction errors or defects, even though he actually does not have as much control as he normally would. it's really a niche for older retired contractors, it would just be an overwhelming amount of work and potential liability for a younger GC.

I was overconfident after successfully doing numerous value add rehabs when this spring we took on a rehab of a little unit that was listed as built in 1901 (I believe it was really built in 1920s and 1901 was used because they did not know when it was built).  

Doing both flips and BRRRRs, if possible, would prevent you from locking up too much liquidity into a deal or numerous deals, thus allowing you to continue to scale.

It happened numerous times after that.

After researching further though on social media and then criminal records I found about 12 previous arrests and numerous convictions burglary, theft, criminal trafficking, molestation (don't think convicted), battery. 

Not sure what state you are, but here your lease wouldn't be "void"  Anything that conflicts with the code would be (landlord-tenant code supersedes leases in DE anyway)I would just say you had them sign an older version of your lease in error and need them on the current one.

I've seen numerous courses offered on Youtube but I am a little sceptical of those.

Most loan packages include something you sign that says that you will cooperate with them to correct any technical errors like this and I believe it also includes the ability for them to sign for you if you don't but obviously they prefer to have clean paperwork where you have signed it. 

If not, there could be numerous chains of the contract which can convolute things.

Also see if you can pull up rental  and sold comps in the area using Zillow and Redfin and you have to give a   margin of error in their estimates and see if property appreciation is there for that area in case you are thinking of building equity.