The Official Intellivision Rarity & Price Guide is the result of a long term research made by monitoring eBay auctions and classic game stores in US, Canada, Japan and Europe. The Guide is born to solve a major problem of collectors: catalog the huge amount of games and collectibles available, offering a serious and documented study of rarity value.
The Guide is a work in progress and it will be updated continuously to provide the definitive reference for all the collectors and sellers: a scientific instrument based on REAL auctions and REAL selling.

The "real" value of a collection
Do you know which is the “real” value of your collection? Do you know how difficult is to find a specific game, how many months do you have to plan for the research?
Well, you know that some of your games are “rare”, but do you know exactly how much other collectors would offer you to buy them? This Guide is the work done by a collector for collectors, to give you all those informations, that are hard to find and that are usually not updated in Internet.
Collectors are often not able to evaluate the price requested by vendors. The risk to waste money for hypothetic “rare” carts or, at opposite, to lose a good opportunity is just too high.Vendors are as well not always aware of the value of items that they find.
This Guide would give you the most up to date and correct indications concerning your personal Intellivision collection: next time you will look for a game, if you want to understand whether you found a good opportunity, or if you don’t want to pay unreasonable money, you know you’ve to consult the Official Guide! Or, you may be in the right place to discover that you own a treasure without being aware of it.

Recording the "real" selling of games
The process followed by this guide is simple: we record real selling of games!
We are considering eBay auctions as the main reference, but also some of the most famous online retrostores.
The price registered in eBay is more relevant for us because this is the price that people pay for real, not just a guess, so it tells us the maximum that collectors intend to pay for any item.
The recording of data is done weekly and it is a never ending process, to guarantee the reliability of data.

The Price Guide
To evaluate the price ranking, we follow some rules:

1. Recording of the 20 best prices ever
2. Average calculation of price based on history
3. We only consider games sold as complete with box
4. The price must refer to a closed auction if found in eBay

The Rarity Guide
To evaluate the rarity ranking, we use an accurate procedure:

1. All items are classified in a six levels list, including Common items, Uncommon items, Rare items, Extremely Rare items, Unbelievable Rare items and Prototypes
2. Starting point of this classification is the average evaluation of the three most accurate rarity lists available: the Hot Spot List of Games, the Tom Heroes Rarity List and the Digital Press Collector’s Guide
3. The initial ranking is modified periodically by considering the average number of items-per-month showing at ebay/stores during the last 12 months