That first link is for a bills + 6 keys, not just 6 keys

First link is actually bill's + 6 keys.

More proof

First link is asking for 12, and your 3 tens are either young, unbumped at all or have received adds in a very short time.

Not enough proof to support low-end

3 links? You need way more

You need more than 3 links for 10 keys.

I had a gold BMOC for sale for 11 keys. Sold it for 13 keys in strange items.

I should resuggest at 10.5 - 11 keys

3 links @ 10 keys from which:

L1 - Has an add

L2 - Sold (quick)

L3 - Bumped a couple of times max

Not enough, IMO.

10 keys is quicksell at the moment. Lots of people are willing to buy at that price, so they move fast.

Vote: -

Both of the valid 10 key links are pretty young. In addition, there are 15 pages of unpainted B.M.O.C's on outpost. If you went through every single one of those 300 or so trades and only found 2 trades in which they were selling for 10 keys, that's not enough to justify a drop. In addition, the prices listed on this website are intended for unmodified items only. In fact, even though these people have free paint, they're still selling for 11 keys. Unless painted ones are in line with unpainted ones to justify your range, they're not really valid proof. Like your mint one. That's valid. All your free paint ones are just proving that people give away free paint. In addition, paint on B.M.O.C's are even less of a concern because they are generally pretty high in price. This is such a commonly traded item that it needs a bit more proof

TL;DR Not enough proof

As in the comments, too few links for 10 keys and it's looking like a quicksell from what has been provided.

Closing for insufficient evidence of low range