I'm looking at the availability tab at top of my hosted website. It shows a gray box which indicates holidays. However, neither Memorial Day nor the 4th of July seem to be gray for that column. Is this International? Do I have to throw a setting to make this work?
Yep, those are driven off the holidays you select in the system.
Go to Settings > Holiday Lists and subscribe to some (and/or add your own custom holidays).
I am a little surprised given the importance of Mother's Day and Valentine's Day in the vacation rental industry, that is is not a default holiday.
I realize that it is not a day off/formal holiday, but they can be huge travel days for VRs.
Anyway how do I set up a custom holiday that will always be the second Sunday of each May? (Mother's Day - USA) and third Sunday in June (Father's Day)?
Yep, the holiday list right now is official federal holidays, but there are so many more lists we could add. Do you know of a standard list of vacation rental industry holidays for US or elsewhere? That's the other side of it -- holidays vary so much based on location some things like Christmas and Valentines day are nearly universal but many others are not.
You can't set a repeating holiday based on day of month. They're all based on dates of year because most tend to change. What you'd do is create one and fill out say 10 years of dates.
I don't know other major celebration days, but mothers day and valentines day are pretty big in the bed & breakfast circles. Not a good weekend to be discounting.