Since he still maintains an interest in the property, beneficial interest in the property has not been transferred, and the due-on-sale clause is not triggered.

Back when I was first introduced to RE transactions, when dinosaurs roamed the earth, there was a clause in the code on installment sales along the lines of; on an installment sale, if you received more 30% or so of the sales price in one year, it triggered the taxes due on the entire gain, even though not received yet.  

I started 5 new partnerships with different investors (4 as cash/credit partners, 1 as a credit partner) to make purchases together in the market I’m already investing in, Milwaukee. 4 of my new partners have been actively educating themselves about REI, but just hadn’t pulled the trigger yet.

Painting over is considered encapsulation and doesn't trigger anything.Keep in mind you can test, but testing means EVERY painted surface in the property.

If, after getting the refi figures, it still only calculates out as a marginal investment (or a loser), pull the trigger, say NEXT, and unload the property and headaches.  

Once an offer gets presented it will trigger assessments on the property.

You probably also know this, but only pull the trigger on a deal that looks great- I've bought seven so far, and only one has turned out to be as strong a deal as it looked when I bought it, mostly due to exploding rehab costs and insane time delays by poor or over-committed contractors.

Your letter should be both addressed and properly titled to avoid triggering doubts in the minds of the recipient. 

It is because of you whom we all get inspired by...With that in mind, I have a question... as I continue learning about real estate investing, I find myself needing to pull to trigger and start.

Generally, the liability of a guarantor is triggered only on the default of the lessee, where as co-signers are equally liable for all lease obligations.