If the seller or tenants refuse to do this, then you can ask the seller to put 45 days of PITI + expenses in escrow with the remaining balance refundable back to the seller if the tenants move out earlier than 45 days (this however, does not guarantee that the tenants will move out within 45 days but it does put pressure on the now seller/landlord to push for option 1 - having the tenants sign something). 

However, we aren't feeling any pressure to get a deal. 

This as opposed to feeling the pressure of having to know everything before you do anything - that's often overwhelming and distracting.

Otherwise from a portfolio standpoint there is going to be some pressure to exit the loans by month 36 which could cost the return some performance return.  

I'm pretty sure I could research and find the correct/safe/legal (as you all seem to put it) manner in which to remove/dispose of these potentially hazardous materials along with the right chemical/cleaning agent to pressure wash any meth residue from the structure's skeleton...With all that said, it doesn't seem like much fun and I think I will pass on this deal, and by the way I would be giving the same advice as everyone here if some anonymous "investor" asked about this online... so I appreciate the words of wisdom.The thing that isn't clear to me is: would I, or would I not be breaking the law by continuing with my "plan"?

However, I went to the first meeting and the main speaker was an out-of-town guy giving a super high-pressure sales job for some MLM program called "Financial Education Services Protection", which didn't actually have anything to do with real estate, other than he was pitching us to pressure credit challenged prospects into buying this (my opinion) predatory program.

What contracts should be used in order to cover both sides and certainly make your prospective lender at ease of the situation?

Don't feel pressured to learn it all at once, but learn what you need to know to do something and go from there. 

Your posts have eased some of my concerns.  

We can add a few extra brains to figuring out a solution, but waiting to call us adds time pressure that's not helpful.