Yours appears to be a business-purpose (investment) loan.

I've been toying with the idea of adding an ISA to my sales business.

You have every right to be outraged at the offending party and that's the tenant.Stay focused on what matters and that is getting back in business. 

. :) Wishing you the best in your business. 

It's easy to bite off more than you can chew in this business and that's especially not a good idea for your first deal.

As good as offsetting all his W-2 / Business income?

Attend local builder associations or networking events, and focus on small contractors or businesses without in-house permit expertise.Highlight how you save time and ensure compliance—it’s a big value-add.

Hi Davis,I live in NC but invest primarily in Greenville SC / upstate with my business partners. 

Now I'm banned for spamming and while I'd like to handle this privately I'm blocked from the messaging system. 

Your question has been debated between BP tax experts both privately and publicly, for example here: https://www.biggerpockets.com/forums/51/topics/819991-expens...And we ended up where we started: no consensus and no clarity.There have also been court decisions that support my interpretation, even though I personally find these court decisions debatable.