They are usually fully booked - it's in San Francisco.

Build yourself a Google business page, make yourself easily bookable on Airbnb (did you know that 25% of nights booked on Airbnb are for 30 day stays and more? 

I’d also love any recommendations for beginner-friendly books, podcasts, or other resources that are suitable for a teenager. 

Listen to the BiggerPockets podcast for expert advice, read books like "The Book on Rental Property Investing" and "Set for Life" by Scott Trench, and join local real estate investing groups or meetups.

It is very complicated; like a snowflake, each transaction is different.How do you decide risk vs. reward here?

It's a great way to give them a better sense of the space, especially if they're on the fence about booking.

If I cancel an escrow, inspection fees or other costs associated with that failed transaction go in here.

I wouldn't worry too much about it, if you have a competent CPA or bookkeeper they should be able to review your books and within minutes have a strong grasp on who gets a 1099 (spoiler alert, not every contractor gets one, I'll be annoyed if I get one since I'm structured as an S corporation) and the amounts to report.1099 filings are usually a loss leader for us, so if you're working with a professional make sure you take advantage of them filing everything for you.

The combined transactional costs alone between the purchase and sale are going to be north of 10% of the transaction value.

Check out the book "Long-Distance Real Estate Investing" by David Greene.