I sent Sierra a 2004 Topps Cracker Jack 'set card' and $10, which is his apparent fee to sign things TTM - maybe it's been a thing where I've sent out less TTM requests over the past couple of years and might need to add $5 or $10 to more requests in order to get something signed.
On the other hand I do not really mind when subjects charge outright, rather than through a middleman or promoter - where it might be fun to see what results I get from a guy like Sierra, who I've never had TTM history with.
I would have also liked to also get a 1990 Leaf signed, but did not have the card in-hand - so I might end up looking for one that is already inked up.