My experience so far
-$60 for my Home Despot mash tun.
-$90 for a 2-port brew pot
-$50 for a basic outdoor propane burner
-$50 in misc supplies that I didn't need for doing full-boil stovetop batches
So, let's say $250 in basic equipment for doing all grain.
I then spent $80 on grains, hops, yeast, etc. That's enough for an IPA, a Pale Ale a Stout and Rye PA, with a leftover pack of Safale lager yeast for a yet undecided project.
So, let's say $20 per batch including yeast and sanitizer
Each 5.5 gallon batch works out to be about 2.5 cases worth of beer (based on the standard 341ml bottle here in canada)
A case of rotgut adjunct lager like Laker is 26.40 per case including bottle deposit. This works out to $1.10 per beer including deposit or $1 after bottle return. 2.5 cases (60 bottles) would run me $60 .
Comparing those numbers, I get an operating 'profit' of $40 per batch, or to put in in easy terms, my equipment will pay for itself inside of 7 batches.
Now, this doesn't take into account the fact i've also started kegging as a direct result of starting all grain... A good quality pressure tested corny costs me about $70-$75 shipped to my front door with taxes in, 2.5 cases of PET bottles costs me $30 without caps, 36.6 with caps, and once we include taxes i'm in to about $42 per batch to bottle in PET. I've grown to hate PET for doing anything but quick "drink it now" batches. so the extra $30 for a corny is well spent.
Even adding in the complete cost of my kegging setup (to be completed soon), with new fridge, stainless tap tower with perlick faucets, 3 kegs to keep one constantly waiting in the wings, CO2 tank, reg, etc, my setup will still pay for itself within 15 batches over buying crappy commercial beer.
I also buy premilled grain right now too, so as soon as I get my own mill, my costs will shrink again.