Selling a LEGO® collection you inherited: what to do first, and what not to do

If you have inherited a LEGO® collection, the first thing to do is nothing. Do not throw anything away, do not open any sealed boxes, do not let anyone take a few sets to "see what they are worth", and do not sell it by weight because somebody said that is what you do with LEGO. A collection built by someone who cared about it is usually worth a good deal more than it looks, the value is concentrated in a handful of boxes you cannot pick out by eye, and every one of those mistakes is permanent.

This guide is for executors, family members and anyone else who has ended up responsible for a collection they did not build. It covers what to protect, how to work out what is actually there, what the estate may need from you, and how to sell it without getting caught out.

Why is an inherited collection different from selling your own?

Three reasons, and they pull in different directions.

First, you do not know what is there. The person who built the collection knew every set, knew which ones were hard to find, and knew which boxes had been opened. That knowledge died with them or moved away with them. You are starting from a pile of cardboard.

Second, you are usually acting for other people. If the collection is part of an estate, the money belongs to the beneficiaries and the executor has a duty to get a fair price for it and to be able to show that they did. Even outside a formal estate, there are often siblings or a surviving partner with a view on what should happen to it.

Third, there is the emotional weight. A collection is not just stock. It is a room somebody spent their evenings in. That is a reason to take your time, and it is also a reason not to let sentiment push you into decisions you would not make with a clear head, in either direction.

What should you do in the first week?

Protect it, record it, and change nothing.

1. Leave it where it is if the storage is reasonable

If the collection is in a dry room, out of direct sunlight, leave it there while you work out what to do. If it is in a loft, a garage, a conservatory or anywhere damp, move it to a dry room, flat, with the heaviest boxes at the bottom of any stack. Do not put it in a storage unit until you have listed it, because listing a collection you cannot get at is miserable.

2. Photograph everything before you touch it

Wide shots of every shelf and stack, then closer shots of each group of boxes with the fronts visible. This costs ten minutes and it gives you a record of what was there on day one, which matters if anyone later asks. It also lets you send a first picture to a buyer without moving a single box.

3. Do not open anything

A sealed box is worth more sealed, in every case, without exception. If you want to know what is inside, the set number on the front and a quick search will tell you. If you want to know whether it is complete, a sealed set is complete by definition. The guide on sealed, opened and loose LEGO explains why the seal matters as much as it does.

4. Do not throw anything away

Not the empty boxes, not the instruction booklets in a drawer, not the carrier bag of loose figures, not the receipts. Empty boxes and instructions are bought by builders who have the bricks and not the paperwork. Loose minifigures can be worth more than the bricks around them. Receipts are worth nothing to a buyer but they can help you identify sets. Clear nothing until every item is on a list.

5. Do not let it be picked over

This is the awkward one. A relative, a friend of the family or a neighbour who "knows about LEGO" offers to take a few sets away to look at them, or to sell them on your behalf. Say no, politely, until the whole collection is listed and you know what you have. The sets that leave first are, in our experience, never the least valuable ones, and it is very hard to get a fair total for a collection when the best pieces are already gone.

How do you work out what is actually there?

By set number. Every LEGO set has a number printed on the front of the box, usually near one of the bottom corners, between four and seven digits long. That number is the key to everything: what the set is, when it was made, when it stopped being made, and what sealed copies have recently sold for.

The job is to write down every number and how many of each there are. A phone note or a spreadsheet is fine. Add one word for condition: sealed, opened or loose. That is the whole list, and with it a specialist can tell you within a few hours what you are dealing with.

If a box has no number visible, has worn through, or is a much older set with different packaging, the guide on writing a set list without the numbers covers the other ways to identify it, including the barcode and the instruction booklets.

Once you have the list, look up sold prices, not asking prices, for the ten or fifteen biggest or oldest boxes. You are not trying to value the collection yourself. You are trying to find out whether you are dealing with a few hundred pounds or a five figure sum, because that changes how carefully the rest of the process needs to be handled.

What is usually valuable, and what usually is not?

You cannot tell by size and you cannot tell by age, but there are patterns.

Sets that have stopped being made and were popular when they were on sale tend to hold their value best, especially the large display models: the big Star Wars ships, the modular buildings, the Technic supercars, the Icons and Creator Expert ranges. A sealed example of one of those is the kind of box that can be worth more than a car boot full of everything else.

Sets still on sale in shops are worth roughly what the shops charge, or less, because anyone can buy them new. Small sets and polybags add up but rarely carry the collection. Loose bricks are sold by weight whatever sets they came from.

The honest answer for any individual box is that you look up what it has recently sold for, and the guide on how a LEGO collection is valued explains how to do that properly. What we would ask you to take from this section is only this: assume the value is concentrated, assume you cannot see where, and treat every sealed box as potentially the important one until the list says otherwise.

What does the estate need from you?

This section is general, and the person to ask about your particular situation is the solicitor dealing with the estate. What follows is what comes up most often when we buy from executors.

• A record of what was there. Your photographs and your set list are exactly this. Keep them.
• A record of what it sold for. If you sell to a business, you will get an invoice or a written offer with the figure on it. If you sell privately, keep the listings and the payment records. An executor may need to show that the collection was sold for a fair price.
• Possibly a written valuation. Depending on the size of the estate and the size of the collection, the solicitor may want a valuation in writing before anything is sold. Ask before you sell, because it is much easier to value a collection that is still in the room than one that has already gone.
• Agreement from the people it belongs to. If the collection was left to more than one person, or the will does not mention it, make sure everyone with a claim on it knows it is being sold and agrees. A sale that has to be unpicked later helps nobody.

None of this is difficult. It mostly comes down to keeping the list and the paperwork, and asking the solicitor one question before you start rather than after you have finished.

Should you sell it as one lot or piece by piece?

Both are legitimate. They are different trades, and which one suits you depends on what you want from the process.

Selling set by set gets closest to the full retail value and costs months of evenings. For an executor with a house to clear and beneficiaries waiting, that is often not a trade worth making. Selling the lot to a specialist gets one figure, one payment and one collection date, in exchange for the buyer taking a margin for doing the work. Neither is wrong. What matters is choosing on purpose.

Whichever route you take, the list is the thing that protects you. A buyer who will not quote from a list, or who wants to "have a look and make an offer" before you have one, is asking you to sell blind.

What about the sets you want to keep?

Keep them. Nobody who buys collections for a living will be surprised or offended that a family wants to hold on to a few boxes, and it is far better to decide that before the list goes out than to change your mind after a price has been agreed.

Two practical notes. Pull the sets you are keeping out of the pile and off the list before you ask for a price, so the figure you receive is for what is actually being sold. And if a keepsake is a sealed box, think about where it will live, because a sealed set on a sunny windowsill fades, and in ten years a family keepsake that has become a faded box is a small sadness that a shelf in a dark room would have prevented.

What to do, in order

Common questions

You do not. Kept dry and out of the sun, a LEGO collection loses nothing in a few months. Take the time to list it properly.

Yes, if you want an accurate price. Start with the biggest boxes, because the value usually sits there, and work down. Most buyers will price a partial list as a partial list and tell you so.

Usually not. Get a few boxes down, look at them in daylight, and check the corners and edges for warping. Most loft collections are in better condition than their owners fear.

A rough range, yes. A firm figure needs a list with set numbers. Photographs are a good way to start the conversation.

Not to give a price from a list. Condition is checked at collection, which is also when payment happens, so nothing changes hands until both sides have seen what they are getting.

No. A built set with its box and instructions is an opened set, which has a real market with builders. It is priced differently from sealed, not written off.

Then you are in a good position. Use it as the starting list and check it against the shelves, because collections change after the last time a spreadsheet was updated.

Written by Peter Pilling, BuyMyBricks, 10 September 2026. LEGO® is a trademark of the LEGO Group, which does not sponsor, authorise or endorse this site. Nothing in this guide is legal or tax advice. Questions about probate, valuations for an estate and who is entitled to the proceeds of a sale should go to the solicitor dealing with the estate.