I'm going to dig a bit deeper than all the other post's answering the OP's questions. Every post so far will help him with a
per round" formula for his shooting...but does that answer his question fully, only he can answer that.
First of all ask your self how many rounds you plan on reloading a year and what type of shooting will you do with the loaded ammo, how much you reload a year will make a huge difference in amortizing the total cost of reloading...reloading equipment/start-up costs must be taken into consideration as a starting point. The type of shooting you do also makes a difference in "factory ammo" costs, Very good "hunting" or plinking ammo can be purchased anywhere now days at reasonable cost if you only shoot a box a year, even at that rate of use the "designer brand" ammo is cheaper than a loading outfit...the cost savings is in lots of ammo use & readily available target quality ammo if that is where your interest lies.
As an example, in my case I have "way north" of $5-7,000 in my loading room construction & equipment not counting actual components...it is a very comfortable setup for my needs and if I amortize that over the 150,000 (mostly .38 sp.) rounds that I have recorded loading in my record book, it ain't much per round. I am currently loading the wife's cowboy rounds (commercial hard-cast slugs) for around $0.12 per, so over 40 years I have saved thousands in ammo costs.
If the OP buys a mediocre $500 loading set-up but only loads 100 rounds a year it becomes "just a hobby" with not much "savings" involved.