Your understanding of the depreciation recapture process is almost correct, but there's a minor error in your calculation.When you buy a house for $300,000, with $100,000 attributed to the land value, you have $200,000 allocated to the building or improvement value.

The sharks at the meetups will be obvious avoid them and build relationship with everyone else.

Unless you also had plans for new builds in the near future, in my opinion, there's much better investment options available in the immediate area

What are the pros and cons of building from scratch for the purpose of STR?

My question is while I was looking on redfin, I found a big 14-unit buildings that is for sale around $3 Million.

The main thing you will need to do before renovating any house or building is to make sure you have a good team in place (an administrator or a licensed care home manager).

I've reached the point where I'm ready to partner up! 

You don't want to rush to partner just to get your next property.If I was new again now and didn't have the capital to get my second one, I would go to every meetup in my area, meet other investors, and build relationships.

Build the relationship with them.

After freshening it up and getting it rent-ready, I was able to list it two weeks ago.I've had a decent amount of interest, two open house showings with about 6-8 different potential tenants/couples.