Recent Case Studies

On paper this is not an obvious investment set. It is not a Modular Building, the line with the longest record of appreciation. It was a mid-priced licensed set, widely stocked, and there were plenty of copies around while it was on sale.

What mattered was how it was built. The shop has connecting sides, so it slots directly onto the other Diagon Alley buildings the LEGO Group has released since, such as Ollivanders and Madam Malkin's. It is a modular building in everything but name. LEGO has kept extending that street, and every new shop it adds creates new collectors who want the whole row.

Those collectors cannot buy this shop from LEGO any more. They have to buy it from someone who held one back. That is the demand behind the price: people who want a street with no gap in it, not speculators.

The Ultimate Collector Series is the line LEGO builds for adult Star Wars collectors: very large, display-grade, and each subject tends to get one UCS version a decade or less. This is the only UCS AT-AT there has been, and the AT-AT is one of the most recognisable machines in the films.

It was on sale for just over three years, so a lot of copies were sold, and a fast jump was never likely. What a set like this does is climb steadily once new stock is gone, because the people who want it are adults who missed it and have the means to pay for it.

At £735 a set, a gain of 27% is about £200 per copy, which is nearly double the cash gain the Weasleys' shop has produced on a set that cost a ninth of the price. Percentage and pounds tell different stories, and a portfolio needs both kinds of set.

The Spring Festival sets are LEGO's annual Lunar New Year line, released every year since 2019. Each one is on sale for roughly a year and is then gone for good, and the line is collected as a series, so demand for the earlier sets does not fade when the next one arrives. The first of them, the 2019 New Year's Eve Dinner, still trades well above its retail price.

This one has thirteen minifigures for £89.99, an unusually high count for the price. In our data, sets that carry a large share of their value in minifigures have been among the strongest performers once retired, because the figures are what collectors and completists pay for when a set is no longer in the shops.

It also displays well: a traditional restaurant with a kitchen, dining room and reception, which appeals to adult builders as much as to families celebrating the festival.