But I think any experienced investor would agree that if you aren't doing value-add when it comes to real estate investing, you aren't actually investing.

I am new to real estate investing and looking to connect with any local investor. 

Then you can read a more in-depth book like The Book On Rental Property Investing by Brandon Turner or The Unofficial Guide to Real Estate Investing by Spencer Strauss.2.

Did you work with any real estate professionals (agents, lenders, etc.) that you'd recommend to others?

Since this situation was so egregious (IMO), I would either boot them out now, or at least have a serious talk, real serious....If you're going to let them stay I would just get a really deep cleaning done, maybe a couple, and then replace carpet after they're gone.

As @Chris Seveney there are lots of buyers for the real estate backed notes but fewer for the business only notes (without real estate as collateral). 

You can also check meetup.com or search Facebook for real estate investment groups, clubs, or meetings in your area.

Eventually, I found real estate syndications and became a full time passive investor.  

I partnered with an experienced STR agent, Troy Nowak, and purchased my first short-term rental in Palm Harbor at the height of the real estate frenzy, navigating fierce competition and ultimately overcoming What made you interested in investing in this type of deal?

Quote from @Joshua Tucker: What specific tax benefits can high net worth individuals receive from building real estate on tribal land?