Are they really safe?

But of most of the deals I've analyzed, (assuming I'm budgeting for safe 10% maintenance and "regular" rates of tenant vacancy - 5% or 1/20 months), there's no way to achieve those sorts of returns, even with a 80% LTV leveraged position.So am I missing something?

I think the beltline is a very safe investment for a buy and hold, but not necessarily for flips.  

So i would want to throw in another $10,000 just to be on the safe side of things.

There are techniques to get high occupancy rates.

And by good, I'm referring to solid, safe and working class neighborhoods (i.e. no warzones). 

I self manage a handful so it gives my maids enough time to clean the entire premises during the same day check-in bookings ( however do not be surprised if you get multiple requests from your next guest to check in earlier).I like to make it as easy and painless as possible for my guests, so my only instructions are to lock up on the way out,  PLEASE do not forget the pool key, and have a safe flight/ travels back home. 

But always felt safe and welcome.

But the "play it safe and careful" just doesnt fit my character.

Better safe than sorry.