These ratings are intended to give an approximate guide to the relative scarcity of worldwide SMS games. They were compiled from the combined experience of several dedicated collectors and from tracking over 30,000 games sold on eBay over a six-month period.
While they are intended to be as accuarte as possible, please note that they should be treated only as a guideline, especially in regards to the different regions - a European-based collector will naturally find European games much easier to find than American or Brazilian releases.

Also bear in mind that while some games may seem very hard to find, there are only a tiny number of titles that deserve serious expenditure. A patient collector can find 99% of all SMS games for £15 ($30) or less, and the vast majority of those will be under £5/$10.