Set 42666
Cat Birthday Party & Tree House
On shelves nowRetail price$29.99What LEGO charged
Worth now$24.99Typical sealed asking price · 43 listings
Recently sold—No recent sales on file
vs retail−17%Worth less than shop price
Not at retail
At $30 retail there's no margin left — pay under $6.
How much is LEGO 42666 Cat Birthday Party & Tree House worth?
LEGO 42666 Cat Birthday Party & Tree House is worth about $24.99 sealed right now, based on 43 live sealed listings on eBay. That's 17% below its $29.99 retail price. It came out in 2025 with 321 pieces and 2 minifigures. It's still sold in shops. Over the last 88 days its typical asking price has fallen 2%, from $25.62 to $24.99. We last checked it yesterday.
Price history
Value history
Oct 26$2543 listings
- Lowest
- $25
- Highest
- $28
- Change
- 0%
- Asking vs retail
- -17%
27 observations · median asking · rechecked 8× daily
Should you buy it?
43 listings behind this — one of the better-evidenced values on the site.
If you bought it to resell
Sells sealed for$25
Marketplace fees · 15.25%−$4
Payment processing · 2.9% + $0.30−$1
Shipping · est. from 321 pieces−$13
Reaches you$7
Pay no more than$5
For a 30% return at your costs. Change them and every figure on the site follows.
How long has it been on shelves?
Still early — released 2025, and sets like this usually run about 3 years. No hurry.
LEGO never announces retirement dates. This is only how long the set has been available against how long sets of its size usually run — not a prediction, and not inside information.
Set details
- Set number
- 42666
- Theme
- Friends
- Released
- 2025
- Status
- On shelves now
- Pieces
- 321
- Minifigures
- 2
- Retail price
- $29.99
- Value per piece
- $0.078
- Price confidence
- high · 43 listings
- Last checked
- yesterday
Where these numbers come from
eBay43 live listingsThe asking price here — the median of what sellers want right now, $25. Last checked Oct 26.See the listings →BrickLinkPrice guideNo completed sales recorded for this one yet. Last checked Oct 22.Open the price guide →Catalogue321 piecesPiece counts, minifigures, release year and retail price come from Rebrickable and Brickset. Retail was $30.See the catalogue entry →
eBay links are affiliate links — if you buy after clicking, we earn a small commission at no cost to you, and that is what pays for the site. BrickLink has no such programme, so those are plain links. Neither changes what we show or what we say about it.
How to read this. The value is the median of live sealed listings, after removing instructions, empty boxes, used sets, multi-set lots and implausible outliers. Real sale prices usually land below asking, so the buy-below figure is deliberately the conservative end of the range.
More Friends sets from around 2025
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▼ 16% vs retailRetired42669 · 2025Beekeepers' House and Flower GardenFriends · 1,161 pcs$7534 listings · retail $90No retail price on file
▲ 22% vs retail42663 · 2025Friendship Camper Van AdventureFriends · 778 pcs$7336 listings · retail $60Not at retail
▲ 50% vs retailRetired42670 · 2025Heartlake City Apartments and StoresFriends · 2,040 pcs$25524 listings · retail $170Holding value