My response is not an answer for but a reaction to this:
Quote:For those of you who provided constructive critcism, I did lower my prices significantly. I also realize it may be best to join a group specific to some of the specialties of philately I like - plate number coils for example. They offer a chance to sell pncs. The prices are higher but it caters to a niche. Engler stamps is particularly interesting as he focuses on coil stamps with plate number on front and back number behind it. As I wrote in some of my listings that particular area can be tricky to find as the probability of getting is anywhere from 1 in 270 to 1 300 stamps from a roll. For low value denominations the costs aren't too bad (but you are stuck with tons of extras) but when you get to the Forever F;ag stamps for Domestic first class mail, it get expensive. So may migrate some of my items over to niche buyers by joining pnc3.org. Thanks to all those who provided constructive criticism and had me really research the direciton of my selling.
ebay may need to just be a place to sell extras at discount and only a few items a little above face value.
The cost to obtain an item from the original seller (Read USPS Philatelic Agency) carries stamp costs separate from the actual item collected. This refers to the Minimum order requirement. However ,when the item enters the market place those costs are not considered by the buyer, nor should they be. Back when the Scott value for a new issue was twice face value (or more on low denominations) that doubling was built in to cover the costs to the dealer for obtaining the item as presented. New issue catalog value no longer covers the dealer's cost and as a result the new issue dealers have generally vanished. Given the fact new issues can be gotten well below face does not help the matter nor market (see below).
Of course back then dealers would do much business by mail, using the extra stamps you mention you needed to buy, as postage or to service FDCs. Heck some dealers even accepted US full gum postage at a credit of face value for store purchase. My US Zepp set was purchased that way as well as a four figure Finnish stamp.
But today there is little use for the extra stamps you must buy to get the positional pieces. What dealers still produce mail order price lists and and do mail order? Those extra stamps currently trade at 20-25% face as scrap or 30% as full panes--Yes, this includes forever stamps. Your extra coil material is scrap. If you want 100% of face, use them mailing out your sold material to recoup some of your costs.
Now as a buyer, where your cost don't matter, only the price of the item I am buying matters, all things equal I will buy from the lost cost seller. I also know that my true cost of a purchase will include the item price, sales taxes any other costs associated with finding the item (gas, parking, entrance fee) and delivery of same to my home, be it postage, gasoline, Uber or bus fare. Sometimes the costs can include airfare, hotel, food and other routine travel expenses. As the seller, none of my costs are of a concern to you.
This now leads me to your question, "Any Tips To Improve Selling Your Extra Stamps On Platforms Such As
ebay?" Pay people more money to buy your items. You already pay folks for your time by giving it away for free. Now reduce the price of the item to be below
any other seller and don't charge postage on purchases. That way you are paying the buyer for your time, paying for some of the face value and all of the postage. That will still not make it certain your item will sell. While a specialist may stumble upon your material and buy it. Some folks may find and buy your material to use as postage if the discount from face is low enough.
I don't think you understand that specialty material can take a long time to sell on
ebay, no matter the current fair market price. I have been watching one specialty item cycle from a large retail dealer and
ebay seller for over 5 years at a price of $3000 which is under catalog but alas over market. During all of that time no other single example has hit the market, a large set (five figures) which included an example of the single item but you needed to buy the set. In the same vein, you have mentioned the selling price of some other dealers. But frankly that is useless information to you. The real question is, "when was the last time they sold an item at that price?"