Percentage Summary: Beckett's pricing and grading lists the condition required for 100% BV, and then sort of drops pricing drastically down to 50% BV. I smoothed out the pricing more from 0% to 100% more, trying to stay close to the ranges provided by Beckett's percentages for lower grades. Then I adjusted the scale up or down based on my actuals from buying and selling either online or at card shows.
2000-present: At some point around this era, cards should be held to a higher standard for receiving 100% of book value. No one is going to pay 100% book value for modern high-technology cards in NM-MT 8.0 condition, which have flaws. I raised the requirement to MT 9.0 for 100% BV, which is a full grade above Beckett's recommendation. Cards are too readily available in higher grades today than in previous years. Cards from 2001-2003 might more appropriately fit into the previous category since there are indeed more difficult to find in top condition due to unopened material being all stuck together.
1987-1999: I changed the start date to coincide with the year where many factory sets and other unopened material can still be found at a very affordable price. This means that better condition cards can more easily be found than form earlier years. The end date for this category was more arbitrarily selected to coincide with the end of the millennium here. The category can be further broken down into 2-3 sub-categories of 1987-1992 and 1993-1999, with 1992-1994 representing transition years between glossy vs. non-glossy, non-series releases vs. series releases, and wax packs vs. foil packs.
1974-1986: I changed this category start date to coincide with the availability of factory sets and end of set releases by "series". Wax packs from this era contained cards from the entire set, which ended the variability of condition and card availability between set years, except for a few double prints. I chose to end this category with 1986 to coincide the sharp decline of available factory sets today. Although factory sets were produced for many years between 1974-1986, there are not many available today. 1985-1986 factory sets can still be found at a sharp price increase from the complete set opposed to later years. This category can be further broken down into 2 sub-categories of 1974-1980 and 1981-1986 to coincide with generally accepted end of the vintage era and start of major card company competition.
1957-1973: I shifted the start date of this category back to 1957 to align with the start of the standard-sized card. Beckett's 1959/1960 cut-off seemed arbitrarily set to align with the end of a decade, rather than the condition you'd expect to find cards from that era in. 1959 and 1960 cards are typically found in the same condition at the same price range. 1957 and 1958 cards are somewhat rarer but they are still found to be more closely aligned with 1959-1960 rather than the much larger pre-1957 cards. I chose to end this category with 1973 to more appropriately align with the end of an era of set releases by various "series" and the unavailability of factory sets. This category could actually be broken down into 2 sub-categories of 1957-1965 and 1966-1973 to coincidence with the rising costs of wax packs and the end of the availability of penny packs.
1948-1956: I feel that the category start date is appropriate because there weren't many cards produced between 1942-1947, so the post WWII era of consecutive card production really started with the 1948 Bowman set. I cut the category end date off earlier than Beckett's more arbitrary 1959 date down to 1956 to coincide with the end of non-standardized card size production. This category could actually be broken down into 2 sub-categories of 1948-1951 and 1952-1956.
Pre-1930: I left this category range unchanged for now.
Here's an excerpt from my Superstars and Unlisted Stars list consisting of hall of famers. I use this to help me determine who should be considered at least an "Unlisted Star" when pricing cards. Beckett doesn't always update their Star pricing. For example, Hall-of-Famers Ron Santo and Billy Williams sell for way more than the Minor Star pricing that Beckett gives them. How can any Hall of Famer be considered to be anything less than an unliste star? My full list goes all the way back to Alexander Cartwright and includes every hall of famer, how they got in, when they started, when they finished, when they got in, and what they got in for.
Here is an excerpt of my Semi-stars and Minor Stars list. The divisions here are little more blurred for me than my Stars List. I treat most players that receive over 10% of the HOF vote as at least Semi-Stars. I have to use judgement whether players that receive 5%-10% of the HOF vote are Semi-Stars or Minor Stars. I treat most of the people that receive 1%-5% of the HOF vote as Minor Stars.
Here is my Minor Stars and Commons list. This list includes everyone that has ever received between 1 vote to 1% of the HOF vote. I tend to treat most of the players receiving over 0.5% of the HOF vote as Minor Stars, and then use my own judgement for players receive less than 0.5% of the HOF vote as to whether they are Minor Stars or Commons. Early cards for these players will certainly get more of the Minor Star treatment than later cards.
Below is some pricing I've developed for the Topps Gallery of Champions metal cards collection.