LEGO 3804 Robotics Invention System, Version 2.0 price history & best time to buy

Lowest new price

About average

Now ¥156,200

Period low¥156,200

Average¥156,200

Period high¥156,200

based on 9 days of data

Price over time

Date	Lowest new price	Used avg (BrickLink)
2026-07-24	—	¥31,037
2026-07-23	¥156,200	¥31,037
2026-07-22	¥156,200	¥31,037
2026-07-21	¥156,200	¥31,037
2026-07-20	¥156,200	¥31,037
2026-07-19	¥156,200	¥31,037
2026-07-18	¥156,200	¥31,037
2026-07-17	¥156,200	¥31,037
2026-07-16	¥156,200	¥31,037
2026-07-15	¥156,200	¥31,037

Used avg¥31,037as of 7/24

Buy new

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Used & parts

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Re:GO records the lowest new price (Amazon, Rakuten, Yahoo! Shopping) and the used market average (BrickLink) for LEGO Robotics Invention System, Version 2.0 (3804) every day. The trend tells you whether now is a good time to buy or worth waiting. Retired sets tend to climb, so keep an eye on the used average too.

← See set details & part breakdown

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Prices are as recorded and may differ from the current store price — always check the store. Used averages come from BrickLink sold data. Re:GO is an unofficial service, not affiliated with the LEGO Group.