Is my collection complete?

[steve B]

Without knowing what was made, it's not possible to really be complete.

I'd suspect that if they had matchbooks that went with postcards, there should be a matchbook for each postcard.
I forget how Holiday Inn di those things. I may have stayed in one 40+ years ago.
If it was souvenirs they sold there might not be a matchbook for each postcard.
If they did what most places do with stationery, and left a couple in a drawer or on a table, I'd expect there would be matching sets.

There are probably people who collect Holiday Inn stuff. And they probably know exactly what was available.

[steve B]

I should also say that when I sort of let go of the idea of completeness I got a lot happier with my collecting. The stamps I focused on have some catalog listed items that haven't been seen since the 1930's if they ever existed at all and aren't a misinterpreted random misprint. Being complete is impossible!*

On the other hand, I have found one that was last described in 1932, and probably a cover that was last seen in the 1930s. And have potential examples of two of the never seen but cataloged varieties. I just need to find a second copy to confirm that they're not just weird misprints. That could be a LONG search....

* completeness in that specialty is also for me impossible from a practical standpoint, a couple items were sold in quantities less than 10, and the most recent sale was in 2016 for 150,000.