I lurk particularly in the 1936-1964 proof coins, and the full step nickels, but I think I've now added a new category I will browse. Got this for $71.50 just mere minutes ago as I'm typing this, will be paying by money order. It's a 1910-S peso, ANACS AU-50 details, cleaned. Interestingly enough, it's the first Filipino peso I've owned that was made under U.S. sovereignty. Greysheet vs CPG on AU-50 is $160/210, while XF-45 is $90/120. I figure if I can get $100 out of it, it'd be a great day. Even if I get $80, which is half bid, I'm still making a bit over 10% profit. Overall, I'm comfortable with trying out U.S. Philippines coinage since the Greysheet is pretty well-established on that stuff. Edit: I was strangely the only bidder. I figure for $65, plus $6.50 buyer fee, the coin is worth it.
A very neat coin series I picked up a few of those a few years back ( "US" Peso's and centavos from the filipenas/philippines ) for similar reasons. Mine are all a bit more circulated Apparently they were at one time considered a "US territory" 1910-45 if I remember right.
I think they were actually a US territory starting in 1901, and ending in 1946, but either way, that stat gives us some more "USPI" coinage to collect. I think it's pretty interesting myself, considering I can find quite a bit of it in 25 cent bins. Most of the coins go for at least a $1 Greysheet bid, most more. The question is, though: would this series be both US and foreign? That may be the cherry on top of it all.
Sorry to burst your bubble but these are pretty common so circulated and cleaned they usually go for about $30.
Here is an eBay comp that sold for 90. That was PCGS which probably helped a bit over Anacs although it should not make a big difference with an inexpensive details coin. I think the Anacs example would go for over 30 but under 90. Maybe 60-75 would be about right.
Interestingly enough, I've never actually seen one in person before. I would believe it, though, that some examples, particularly the lower-grade common dates, are sold for around $30. This particular date is by no means a key, but a better date in the high grades. I wouldn't call this very high-grade, but for $71.50, I can always hold it for a while. Looks about like mine. I doubt CDN numbers have changed since April 5th, so I can use this for reference. For me, either PCGS or ANACS works, and no matter what grading service, this may be a series where cleaned examples are significantly less. (Which is what I got it at. )
I looked it up on GC and found that is went for a bit under $45 there. So the eBay person was able to sell it for double (minus fees and shipping of course, but still a solid return).