In the event they wish to go month to month or renew multi-year as opposed to the automatic one year renewal in the lease, should we execute a brand new lease or is it better to do a modification / addendum of sorts to the existing lease simply outlining everything is still in full force and effect and we are simply changing the length of the lease? 

In securities they refer to this as the 'prudent investor' rule.Keep an open dialogue and communicate with your 'lenders'...through good and especially if the ride gets a little rough.Do select and utilize a qualified third party servicer to execute the terms and conditions of your lending agreement. 

client has offered to provide for my safe keeping an executed Quit Claim Deed as added security. ( not worth the paper if I am not first position I think?)

DebtGet a plan in place and start executing.  

Therefore, my Brokerage services for investors is based on formulating a plan of execution from you and I to meet your goals and objectives. i.e.

Other than that, layout a gameplan, give yourself room for error, and execute.

Investors need to build a competent team to be able to execute a profitable flip and have the proper market conditions.The shows are unfortunately a waste of time educationally.  

Eventually I received an almost-valid lease that Seller executed without my written approval (not ok).

We would like to have some agents to work with for finding and executing deals.  

Any particular BiggerPockets threads or podcasts that you feel are best for someone with some knowledge of the industry, but no actual execution yet??