# Robotics Invention System Upgrade Kit #3803 — resale value

Source: JunkPal price guide — https://junkpal.ai/products/robotics-invention-system-upgrade-kit-3803-lego-mindstorms-lego

**Robotics Invention System Upgrade Kit #3803** sells for about **$1,199** new or sealed, based on real closed eBay sales.

Live listings and the full sold-price history are on the page: https://junkpal.ai/products/robotics-invention-system-upgrade-kit-3803-lego-mindstorms-lego

## Value by tier

| Condition | Value (USD) |
| --- | --- |
| Sealed (new) | $1199 |

Values are medians of real closed eBay sales, updated 2026-08-06. They are estimates for reference, not offers or appraisals — condition, completeness and edition move them a lot, so compare against the sold listings before pricing anything.

## Check the market

- [Sold listings on eBay](https://junkpal.ai/api/go?to=https%3A%2F%2Fwww.ebay.com%2Fsch%2Fi.html%3F_nkw%3DLEGO%2520Mindstorms%2520Upgrade%2520Kit%25203803%26LH_Sold%3D1%26LH_Complete%3D1%26mkcid%3D1%26mkrid%3D711-53200-19255-0%26siteid%3D0%26campid%3D5339166094%26toolid%3D10001%26mkevt%3D1%26customid%3Dmd-sold&p=md-sold) — the closed sales these medians are computed from
- [Live listings on eBay](https://junkpal.ai/api/go?to=https%3A%2F%2Fwww.ebay.com%2Fsch%2Fi.html%3F_nkw%3DLEGO%2520Mindstorms%2520Upgrade%2520Kit%25203803%26mkcid%3D1%26mkrid%3D711-53200-19255-0%26siteid%3D0%26campid%3D5339166094%26toolid%3D10001%26mkevt%3D1%26customid%3Dmd-live&p=md-live) — what sellers are asking right now

eBay links are affiliate links: JunkPal may earn a commission at no cost to you.

## Details

| Field | Value |
| --- | --- |
| Brand | LEGO |
| Theme | LEGO Mindstorms |

## Robotics Invention System Upgrade Kit #3803 (LEGO Mindstorms) resale value

A loose Robotics Invention System Upgrade Kit #3803 set runs around null, a complete copy (all pieces + box + instructions) about null, and a factory-sealed box commands $1199.

### What drives the price

Retired sets, completeness (every piece + minifigs + instructions + box), and sealed condition drive LEGO value. Exclusive sets and discontinued themes appreciate the most; minifigs alone can carry significant value.

## FAQ

**Is this LEGO Mindstorms kit new in box?**

Yes, the Robotics Invention System Upgrade Kit #3803 is sealed and brand new.

**What is the theme of this item?**

The theme for this item is LEGO Mindstorms.

**What is the listed price for the sealed kit?**

The sealed, new kit is listed for $1199.

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Full price guide: https://junkpal.ai/products/robotics-invention-system-upgrade-kit-3803-lego-mindstorms-lego
How these values are computed: https://junkpal.ai/methodology
Cite as: "JunkPal price guide value as of 2026-08-06, based on real sold listings (junkpal.ai)"