When DD was 3, it cost €94, her Santa present was a bicycle and her stocking had:
Red apple, green apple, mandarin, kiwi, banana
Chocolate lollipops (M&S ones)
A book
Bottle of bubbles
Spinning top
Nice coin purse
New crayons
When she was 4, it was €130, for a Scooter and her stocking (which I helpfully never wrote down what was in it!).
When she was 5, her main present was a DS and 2 games, so more expensive year, and her stocking had quite a lot of bits and pieces gathered over the year, so it was just over €200, but she used most of it a lot:
Usual fruit and sweets
2 books and an annual
Dressing up things (grass skirt, bangles, Peppa pig glasses case)
Art & craft supplies
A lacing game (to develop hand/eye coordination)
and a new duvet cover
Age 6 we were back to roughly €130, with smaller presents like Operation game and a Mr Maker set, 250 piece jigsaw, some lego, and stocking items.
Fruit and sweets
Buzz Lightyear "magic" facecloth (dehydrated that unfolds in water)
A mini parachute (that only retired in the past 6 months - she's over 12 now)
1 Mr Maker craft set,
book,
dollie nappies, dollie shoes & socks set,
glow in the dark stars,
meccano helicopter,
small jigsaw,
And so on over the years - some years are more expensive than others. Age 7 was another bicycle year, and age 10 was an Xbox (not just because she wanted it, but she'd had a hard hard year and really deserved something special, and we could afford it). Other years have been bits and pieces rather than 1 big thing.
The stockings will always include fruit, sweets and a book amongst the other small things.
And yes, there is a trend towards costs increasing as she gets older - partly inflation, partly that she needs more, and partly we can afford to indulge her a little. But there are no piles heading towards the ceiling - her original stocking along with a few items alongside it is still what Santa leaves.
And it will be an even smaller pile this year as what we think she needs (and wants, in fairness!) is pricey but very small. And she's mostly grown out of lego and jigsaws and the like, so maybe a board game that's suitable but that's probably about it. (And probably the last time "Santa" properly comes anyway).