But what if you could have only one of those items? Uno. A single, measly beautifier to make you look good, or at least better than your unadorned self. What would it be? Which one can't you live without?
And if I had to pick just one? After much deliberation, I voted for eyeliner. What about you?
To find out others' must-haves, I stopped 100 women (and one young man) shopping at Sephora — a chain that carries a head-spinning 200-plus brands of beauty aids at more than 250 locations across the country.
By far the most frequent choice of those I talked to was mascara, picked nearly twice as often as the closest contenders (eyeliner and foundation).
And almost everyone's favorite mascara color — this was true of women of every age, race and hair color — was blackest black.
"Mascara is everything to me. Everybody knows me as the mascara queen," said Haley Rolf, 18, a college student from Minnesota. "I couldn't go anywhere without my mascara. In between classes I just whip it out. It's fun to put on. It soothes me," she says. And, no, she doesn't even need a mirror to apply it.
Asked to pick a single product, Rolf's friend Alisha Magee, 17, said, "Oh, that's hard!" leaning toward mascara but finally voting for eyeliner.
Lacey Moak, 19, loves pear-flavored lip balm that she buys at Gap but her No. 1 choice is NARS blush in "orgasm," a best-seller at Sephora.
Many of the women I talked to were extremely loyal to their brands, ranging from drugstore staples like Maybelline, Neutrogena, CoverGirl and L'Oreal, to high-end labels such as Dior, Make Up Forever, MAC, Smashbox and Chanel.
"DiorShow," proclaimed Chicagoan Jennifer Baker, 27, when asked her mascara choice. "I have to have my lashes — or else. It gives you the drama!"
No women under 40 cited moisturizer as their go-to product. But many in their 50s, 60s and 70s said that moisturizer would be their first choice.
"My mother used Pacquin (moisturizer) every day. She's 91 and she does not have wrinkles," said Jeannie Thompson, 63, a nurse from Muncie, Ind. who moisturizes with Clinique.
The only man I saw make a purchase at Sephora was Simon Bigant, 17, who was visiting from Le Havre, France. He was buying Diesel's Only the Brave men's cologne because it was cheaper here than in Europe.
But when I asked if he had preferences about any other grooming products, he shrugged and shook his head no. "Whatever," he said.
What's the single beauty product you can't live without? Tell me at email@example.com.
*Ellen's 18 must-have beauty essentials:
hair conditioner and gel
liquid foundation and powder foundation
eyeliner and mascara
four shades of eye shadow
lip liner, lipstick, lip gloss
Follow @ellenwarreninfo on Twitter