I have always bought the regular way- with an agent (or representing myself in the state in which I am licensed), on market properties and fair negotiations. 

I'm not an agent, but the lack of investment-savvy agents in my market comes up regularly at my meetup.

There is furniture and stuff in the way and you may miss things, plus they could do damage between when you did the inspection and they actually move out.If they are moving out at the end of the month, tell them you can do a pre move out inspection, but put it in writing that as their belongings are in the property, you may miss things.the link provided earlier for California, says you can do an initial inspection, but it is also followed up by a regular inspection after they move out. 

With regular real estate, escrows with retail buyers fall out all the time and is expected.

,,I suppose there are some regular neighborhoods where a STR would work, but why are people coming?

You'll find an example analysis here: Months Supply.

You’ll also see that various potential investors will start reaching you out regarding investment opportunities once they see you posting regularly about Real Estate on your social media.

We've already agreed on rates, and I'm going to ensure all the paperwork protects me just like it would any other lender (proper contracts, personal guarantee, etc)The part I'm unsure of is what type of entity it should be under, just a regular LLC?

When I was just a regular agent, I didn't get the nuances that investors really needed. 

One of the things I always make note of (whether for my investment properties or for my personal residence as is the case in this purchase) is the type of plumbing for both supply lines and waste/vent stacks.