Here are the top ones: Airbnb, VBRO, Booking.com, and Direct Booking on a property website. 

I’m a fairly new investor, currently with only one STR/MTR duplex in Indiana, and I’m looking to develop new skills in order to improve my personal income to help expedite a second rental investment.I am a touring musician, and also have 5+ years of bookkeeping experience for one of my small businesses, and I run the books for my one duplex as well.

Over the past year or so I've read books, blogs, and watched more YouTube videos than I can remember.

That way, you’ll have control over the operation and might be able to squeeze in a few extra bookings to pad your numbers.

In a lot of ways my wife now runs our business, but she’s never read one book on real estate and never make one post on Bigger Pockets.

I went to the Town Hall and asked if they had a law on the books and spoke with an individual who said my municipality has a "love hate relationship" with vacation rentals. 

She runs all of the books for her multiple investment properties as well as her assisted living business that she owns.

I didn't see a Biggerpockets book on commercial properties (maybe there is one that I didn't find) and I don't know which book to buy or which author to trust on Amazon.

There's gotta be some law on the books that it's a-ok to slap a really stupid person, like at a certain level of idiocy it's a public service vs assault, right, I mean seriously, come on. 

I can't vouch for it, but check out "Real Estate Partnerships" book in the BP library.