People are buying advent calendars and selling off bits on vinted so I would have a look there first.
I recently purchased the lisa eldridge liquid eyeliner for £8, it was from this years spacenk advent.I really like it and have picked up another.
For a palette i would go for natasha denona from vinted some people are selling ones from edits , last years cult beauty advent and also from last years Glossybox at much lower than retail. For setting spray you will also find loads on vinted but I I particularly like makeup forever, urban decay or Mac. I'm currently using the MILK setting spray and would say it's quite good and loads are on vinted.
Mac is my usual go to for lipsticks but I quite like Vieve too and Sisley. Perfume wise I'd go Kayali and get her a mini. For mascara I would consider the brand ilia. For blush I wpuld go for a Patrick Ta duo and again its cropped up in advents this year so lots of vinted.
I would add an eyebrow gel, mascara, eyeliner, eye pencil, her regular foundation, powder, setting spray, liquid blush, contour stick, bronzer, ,powder blush, highlighter, eyeshadow palette, lip liner, lipsticks x3, lip gloss, lip oil, makeup remover so micellar water and cotton pads or reusable ones or makeup wipes. After that a candle, fluffy socks a face mask and some eye patches and a perfume.
So if make a list of what you want tp but, any particular brands you want, check vinted and then other retailers such as Spacenk, Cult beauty, Sephora, boots etc. If you sign up as a new member you will be liable for discounts and can check for a blue light card discount if that works for you.
I'm going to challenge myself to doing this next year for myself and then getting my dh to fill an empty advent calendar I already have.