My lease is really broad but does speak to this. 

I don't have a code reference handy, but IRS publication 598 which covers UBIT related topics does note this exemption.So, a Solo 401(k) is not broadly exempted from UBIT. 

The $2000-$2500 range is a little broad.

Another broad question I have for you guys is that with respect to the renovation and making an offer, how does the process typically work.

That's too broad a question to really get any good answers.

Broadly, I think a lot of people get focused on cashflow because it is easy to track, or seems easy to track at least.

This would also include investing in broad low-fee items within an HSA-qualified health account (these also save on premiums as most folks over-buy health insurance out of ignorance of their options and realistic fees.  

Who knows how things will play out, and I love to see differing viewpoints and opinions as we all bring an array of experience, knowledge, and opinions to a very challenging and complex topic.

@Joe KoonerIt's easy to get sucked into a deep rabbit hole of research/due diligence and really lose the forest for the trees when you're just trying to find out if your goals are broadly achievable.

With a partnership, you have a whole array of moving pieces that you don't have when you're flying solo (e.g.; cost responsibilities, profit sharing, decision making authorities, work responsibilities, contracts & corporate agreements, etc., etc.)