I know it may seem from everyone's eyes that I may be jumping the gun and going in blind, which is fair I have no experience in real estate or STR but I do have experience in business and have had a successful business when I was active in the market I worked in. 

In response, I had a plumber and a water restoration company come to assess the situation.The restoration company cut into the drywall, and the plumber thoroughly inspected all the pipes, performed a leak test, and conducted a pressure test.

Hello! My name is Jared Smith and I have been involved in various real estate investments since 2006 when we did our first flip in the PNW all on a CC! (not recommended). In 2017 we started our journey with long-term ...

Michael Plaks has a great post on this topic.2 - Assess the value of those tax deductions to you: Best way to get that is by working with a real estate tax expert.

There is no sewer easement or anything recorded that my active line is there. 

For those managing active income streams—like wholesaling, flipping, or even running a real estate business—filing as an S-Corp can significantly reduce self-employment taxes.

What actions and/or credentials make a landlord an active property manager to deem rental income/loss active in CA?

I honestly wouldn't even trust anything QB is telling you when it comes to taxes.You're in a partnership, which acts like a conduit to pass through the income/loss of the activity to the individual owners.

Don't try to build a buyer's list with no experience and no active under contract.

It's clear that is something you're actively doing as well!