Long story short, I felt I wasted money, and gave up on the course entirely a month after purchasing.

Liquidity: If this is your first or second property, prioritizing liquidity (by cashing out now) might allow you to seize unexpected opportunities, especially if you’re actively prospecting deals.Since you don’t have a deal lined up yet, you might explore options to minimize the gap, like prequalifying potential deals or using short-term financing strategies to bridge the 4 months.Good luck growing your portfolio!

I'm also in Eugene and have (or have done) flips, long- and short-term rentals, and multifamily.

For the short-term rental self-managers, how much time do you spend managing your STR every week?

Your development deal will look much like a flip in the eyes of the IRS since it is 6-9 months as well you'll have the short-term side of taxes, not the capital gains taxing on it.  

https://www.biggerpockets.com/blog/brrrr-loans-what-are-the-...Short-Term Rental Loans: What Are the Options and How Do DSCR Loans Stack Up?

Short answer: No.

With my increased AirBnB performance, I decided to turn 2 other rental homes into short term rentals and decided it was worth investing in proper training to make sure I was doing it right. 

I probably wouldn’t mention your third point - it makes it sound like you expect them to hold this note forever and I’m not very certain, but I’m guessing there isn’t a huge market for $100k secondary notes.Have you considered asking them to finance 90-100% for a short period of time so you can rehab and refi at a higher valuation?

If they paid Dec rent, then they still owe you for part of Jan (if the lease requires 30 days' notice-if more time is required, then they owe you rent for that period (unless you rent it).