Dan...
Squirrel and Ducks are two different reloading setups, and for starters, you may just want to start with one.
Ducks require steel shot, special steel wads, and frequently different powders. Plus you really need to get 3" (or 3.5") hulls for waterfowl to get enough killing power, unless you use HeviShot. And HeviShot is almost another reloading proposition all by itself. I suggest you set up for loading lead shot before branching out to the more exotic stuff.
Cost:(All prices are Gun Club bulk purchase price from a distributer)
Once fired hulls, Winchester AA 2 3/4" - $40 per thousand.
Wads, Claybuster CB118-12 (less expensive copy of the WAA12) - $5.75 per 500
Red Dot Powder - $12.70 for 1#
Winchester 209 Primers - $99.50 per 5000
Shot - $13.95 for 25# (chilled), or $14.55 (extra hard Mangum shot)
Shotshell machine Bottom end: MEC 600 Jr - $84.85, Middle level, Sizemaster $127.87, Progressive MEC 650 $166.88
Reloading Scale - a must for safety - $25 - $95 for a mechanical one, $150 to $250 for the electronic ones.
I picked Red Dot powder as the cheapest one of many suitable powders, same reason for the Clayabuster wads. A typical load would be 1 1/8 oz of shot, the powder would be 17.5 to 18.5 grains (7000 grains in a pound). (Get your loads from a shotshell load book, not the above example.) From the data above you should work out a cost per round. Expect to lose some shot and powder to spillage, however.
If you buy your components at a gun show, expect to pay more. If your gun club buys in large quanties, you may find additional savings. If you buy your machine used, expect to pay about 1/3 less unless you find a really good deal.
I also suggest that you buy the MultiScale Adjustable charge bar to fit your machine. You have more control on powder and shot volumes, and you will find that different powder lots have different volumes, and chilled and magnum shot have different volumes. The reloading scale must be used to set your charge bar, and is still required if you go the multiple charge bar and powder bushing way.
As a starting approach I suggest you buy the Lyman #4 Shotshell manual and read it and understand the process before you buy anything else. Shotshell loading is different from metallic reloading in that you need to use the specific recipe in the load manuals for everything to turn out right. The loads in the manuals have been pressure tested, and also have enough volume of materials so the load stacks up right and a good crimp can be obtained. Changing a primer type, or a wad, and pressures can skyrocket.
Obviously you'll need to find a gun club that has Trap or Skeet in their programs to take advantage of their purchasing power. It's also a good place to practice, and get help from fellow shotgunners.