With only 26 missing cards away from the 1967 Topps set and 30 missing cards away from the 1966 Topps set, one might think that I'm pretty much already there. Normally, I would tend to agree. Just overpay for a few cards and the sets are complete, right? It's not that simple with these two sets.
The high numbers that I'm referring to are 1966 Topps #523-598 and 1967 Topps #534-609. My gauge for low-end pricing of late-'50s to early-'70s common cards is about 20% of BV (but even lower for stars). This means that I would expect to be able to find a $15.00 BV card online for $3.00 at the low end. It's not guaranteed, but the concept basically holds true for low-grade cards from this era.
However, this is not true for high-number cards from the '67T and '66T sets. Not all $15.00 BV cards are created equal in the '67T set. Low-number '67s with a $15.00 BV can generally be found for under $3.00 (20% BV), but good luck trying to find a high-number '67 with a $15.00 BV for under $3.00 (20% BV).
My experience has been that the pricing in Beckett is understated for high-number '67T and '66T. The pricing that would make the high-numbers more accurate in the guides for high-numbers are:
*1967 Topps: 2x BV
*1966 Topps: 1.5x BV
What this means is that when you're looking at the Beckett Price Guide and it says that a 1967 Topps high number card #534-609 is worth $15.00, it should really say $30.00 (2x BV), which means that you can expect to pay no less than $6.00 (20% BV) regardless of the condition. For a 1966 Topps high-number card #523-598 valued at $15.00, it should really say $22.50 (1.5x BV), and you should expect to pay $4.50 (20% BV) regardless of condition.
This is the math I've developed from my experience purchasing the lowest-grade cards possible. Very rarely do I get luckier than what's stated above. I don't have these issued with any other high-numbers from the '50s, '60s, or '70s. However low-end pricing online seems to rise towards 25% BV after the early-'70s, and drops to 10%-15% BV in the early to mid-'50s (not including '51T, which is way under priced in the guides).
