If they can grab another $100 from every customer and sock it in Treasuries, that's lots of new income for them. 

To be considered by IRS as a short-term rental and get the tax benefits you must meet the following requirements (defined by Treasury Regulation Sec. 1.469-1T(e)(3)(ii)(A))The average period of customer use is 7 days or lessThe average period of customer use is 30 days or less.

https://blog.firstam.com/economics/mind-the-gap-between-mortgage-rates-and-the-10-year-treasury-yield

Treasury yield curve rate for one year, as of the first business day of each year, whichever is greater.

Thanks for the input Joe, it looks like the interest rate is based on the 1 year treasury yield curve, but I'm not sure why they ask for the county.

@David Bilandzija where do you typically go to buy US Treasury bonds ?

If you invest in real estate - congratulations on having goose egg on your tax return on the Pay to the Order of the US Treasury line!

@Bonnie Low please be cautious with HELOCs, most are adjustable rate and float with the 10 year treasury rate.  

Watch the 10-Year-Treasury.

I can offset some of it if I buy $200k worth of CD's or Treasuries and monitor the market but still the cash out would decrease my cash flow by 700-800$.