Everyone thinks it will be fine but it rarely turns out that way.

Do you find it necessary to get one of these licenses or are you fine without them? 

So I ended up getting a commercial line of credit on that same house to the tune of $100K...I used $40K of that to help me buy a 4 plex...so now I'm down $120K in "opportunity cost".

If the optimistic scenario happens I think you'll only pay a little more, but if the pessimistic scenario happens I think you'll pay a lot less.Condos are fine.

And look at the fine print on the loans, a point or so is a fair amount of money over 1M.

Yes you can do it, you just need to make sure that you dont break any licensing laws or you can get fined for practicing real estate sales without a license.

To be honest, this may be a tiny bit above what I thought the house was worth, but if overpaying by a couple thousand dollars to acquire a new rental was what it took, then I was fine with it, as he was going to be financing the deal for me.

Your intentions are very clear, you are off to a fine beginning.

Vacancy, repairs, and management look fine/average.

Would like to fine some single family house to rent.