You go to any store, if a item is going on sale they’ll tell you.
I don't know if just about any store would do that, but when I bought my AR-15, I was told that they were going on sale the next week, and if I paid with my "Military Star" card, I would get an additional 10% off. So it was 10% off on sale, another 10% off with the card, and then the almost 9% off because I bought it at the PX with no state sales tax.
I've started a blog about my car and adventures: http://65mustangfun.blogspot.com/
1965 Fastback, 289, Toploader 4 Speed, owned by me since June 1980. Originally a C-code with a C-4. 5R09C16****