Well, I have a couple appointments with coin dealers today. We will be discussing trading my 40%ers for 90% or silver eagles. However, I am new to the silver game and have zero idea as to what I should expect. What bottom dollar should I have on the worth of my 40%s? What is the top dollar in worth I should be willing to give for 90%s or silver eagles?
My assumption is that by "coin dealers" you mean people who run a physical coin shop. This is just my opinion, obviously, but I would HIGHLY suggest that you stay as far away as possible from coin dealers if you want to sell, trade or purchase coin, bullion, scrap, or currency.
Don’t get me wrong, I’m all for supporting small local businesses. It's quite OK to go to a LCS to buy storage tubes, 2x2 flips, or other supplies.... but NEVER sell, trade or buy coin from them, as your behind will be metaphorically sore for weeks afterwards.
There are alternatives to dealers. Try putting a post up on your local Craig’s list, go to a local antique / collectible / coin auction and simply strike-up conversations with people in attendance, post your stuff on a local metal detecting forum’s “buy/sell/trade” section (if you can for free), do ANYTHING other than deal with coin dealers.
Be patient, be firm, be tenacious and you might be able to trade your 40%ers for 90%ers at a 3-for-1 rate or better (a straight-up trade would be 2.44 to 1, but that isn’t going to happen).
Good luck!