The honest no-bs answer to what it costs is: it depends.
I'd have to say that the price of bullets are the biggest variable. But that variable can be huge. Just a few days ago I paid $54.00 for fifty bullets. On the same day I paid $63.00 for 100. Last week, 1000 bullets for $150.00.
See what I mean?
It may be more illustrative for you to know that on average, a box of 300 BLK that sits on the shelf at $35.00 can be made identically for about ten to fifteen bucks. And the ammo you make, can easily be more consistent (consistency = accuracy).
Presses and peripheral equipment is also a variable, but the closer you can narrow down what you want to do - or not do - the more those variables can be narrowed down in terms of cost.
I know that this is no small task in itself, but if there is some time/day you can catch me sitting still with enough time to go over to the reloading room with you, I can show you basic to exotic and explain the differences to you. JD & Charlie have blessed me with an amazing facility to make/reload ammunition and given me the run of it.
I think that you'd be silly not to take advantage of seeing /fondling the equipment before you start making decisions regarding what to buy or not buy.