I have found motivation through David Greene and his story for the simple fact we have similar backgrounds.

Would a conventional refinance tie me to remaining an owner occupant in my current 4plex for a longer period?

Unlike a HELOC, your minimum monthly payment will remain consistent.  

Better to find out how long they have been renting, any late rents, how many more years remain on the lease etc.

It didn't persuade unmotivated sellers do sell to me, and motivated sellers didn't bother to even look at it, all they cared about was whether or not I was willing to buy.

Motivation for ARM is the lower interest rate & hence more payments towards the principle. 

I just think it is crucial that if someone would be calling potential motivated sellers or other cash buyers on my behalf (therefore representing my company & brand), I need to at least have interviewed them thoroughly and be confident that they would not misrepresent me in any way. 

I want to give a shout out to @James K. for his motivating articles and @Joe Fairless for being in my car every day to teach me something new about multifamily investing via his podcasts.

Do I pay full rent to our partnership so that the investment remains the same on paper as if I wasn't living in it?

I appreciate the motivation.