For starters the stamp listed as Scott 455 is a trimmed sheet stamp. The top and bottom margins are too small and the top margin is crooked. Also, The 456, assuming it has a watermark is a horizontal coil. The perforations are vertical as is the watermark. The top and bottom edges of the stamp listed as 355 don't appear to be exactly parallel. No imperforate 4 or 5 cent horizontal coils were available to be perforated. Fakes are either trimmed sheet stamps or imperforate stamps trimmed by hand and perforated. Usually the edges don't pass because they are not exactly parallel or the characteristics of the trimmed edges lack the characteristics of hand assembled flat plate coils. The 354 appears to have been cut from imperforated stock and perforated. I cannot be 100% sure without examining the perforations under high magnification. Scott 387 is a very scarce stamp, grossly undercataloged. I don't believe this is a 387. The right and left perforations don't have much in common.
I believe that some of the no gum stamps are used. It is not appropriate to describe hinging on a stamp without gum. No gum stamps (except certain early Bureau postage dues) should be soaked and dried flat under light to moderate pressure. (Don't press out grills.) I didn't have time to go through the listings in detail. I did notice some issues with the Scott 76. Either it is reperforated on multiple sides or was cut out of a sheet with scissors. I advise potential buyers not to buy if they see something in the image they don't understand. I certainly don't understand the stain or repair close to the top margin. The stamp should be dipped to determine if any margins were added and checked to make sure that it is not a perforated proof. Also, the 190 with the fake grill is likely to be used. With all of the damage and defects, it would be worth $10 to $20 to an expertizer as reference, assuming that I am correct that it is used.
Also, check the old
http://www.scads.org web site. If any of the listed stamps were bought from any of the dealers mentioned, they are suspect. If you live close to Washington, DC, it is possible to make an appointment to go to the Smithsonian to use the VSC-6000 and other equipment in the lab to examine the stamps for removed cancels, watermarks, repairs and other mischief.
I also was never a believer in "see scan for condition". Although
ebay allows this practice with some limitations, images must be hosted on
ebay. Links off
ebay to substantive elements of the description are not allowed.
Finally, I suggest that the "COMPARE" links go away. I don't see how they can help. Often someone will be dumping some particular stamp at a lower price. To compete, it is necessary to establish a reputation for accurate descriptions and better quality fixed priced stamps.
I hope these comments are useful. I don't normally contact sellers with listings in need of modification because I have to sell in the same marketplace.
Clark