What is a reasonable percentage of face value to pay on e-commerce sites such as
ebay for non-collectible unused excellent condition modern common under 50c FV stamps to be used for postage, whether they be sheets, plate blocks or loose?
Should one pay less for large size common horizontal stamps such as the 29c Elvis, 34c Baseball's Legendary Playing Fields because one can use less on an envelope or package due to size vs the 32c Swan stamps, which are small?
What is a reasonable percentage of face value to pay for common non-collectible higher denomination $1, $2, $5, $10 stamps?
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