NOT COUNTING the cost of a press, dies, and a scale- and assuming you have (or can scrounge) brass-
AROUND $10 per hundred. Here is a calculator you can use-
Handloading Cost Calculator
You can check what it will cost you to buy powder, primers and bullets where you are (you do NOT want to pay shipping on HAZMAT- trust me)
I pulled price of components from local store, used Unique powder, with a middle of the road load, 115 grain Hornady bullet- and got $9.77. Allow for a couple of spoiled rounds, odd penny for case lube, cleaning, etc.
9mm Parabellum is cheap pistol ammo to buy- but you CAN save a buck or two- and make good quality ammo. You really save when you get into some of the more expensive rounds- I have a Winchester 71, caliber .348 Winchester- and when you can find it, it can run $50-$75 per 20 rounds.