These all sound like passive income deals, which would be subject to passive loss limitations. 

You can read all about what the US did in my previous article on the subject here.

The lowest loan amount I've seen allowed is around $55K with minimum property value/purchase price at $75K, just for the subject property. 

One more question, can you use the 5% for 5 units+ or is it subject to the same 1-4 limit?

With interest rates and prices skyrocketing, I believe this strategy has the potential to become a hot trend in our area.My plan is to acquire properties via seller finance or subject to, optimize it for this strategy and then repeat the process to multiply and increase income sources.

"Nice" is subjective.

This could be done through a "subject-to" deal, where the buyer takes over payments on your existing mortgage while you provide financing for the remaining balance.

I wanted to introduce myself as I am incredibly anxious to step foot into the incredible world of REI and would love to know if there are any local investors that meet/would like to meet on a semi-regular basis.I currently have a full time job in outside sales in the Arvada area so I do a lot of driving around which enables me to spend a lot of my time listening to podcasts and educating myself but I would love to get to know some players within my local area to really dive deep into the subject and in which I could potentially be of value in the future.

That said, if the property you're attempting to finance is materially larger than the properties you currently operate (IE - you're trying to finance a 30 unit building, but have only operated a series of 4-plexes to date), then sometimes this rule gets thrown out the window and you'll still be subject to the "Limited Multifamily Experience Sponsor" re-sizing parameters. 

Deductions are a matter of legislative grace and the taxpayer bears the burden of proof, both of production and persuasion.