Honestly, by far my biggest expense in terms of actual coinage is in dechlorinator.
It costs alot to maintain alot of jars and tanks.
But, as for food, food is cheap, and cultures last pretty much forever. I suppose light and heat factor in, I am cheap when it comes to supplies so I have worked out what works best for me (scourning the local buy n sell etc). I usually use halogen lights for my fish and their rooms, those are pricey to buy but cheap to operate and creat great light....Heaters are prob the most expensive after lights, they run me about $16 each for good ones. But in my fishroom I use radiant heat so that room does not require any heaters - and, now that I have moved them to my office they get daylight too. Meds and additives would be the next on the list....
SOME breeders do use two females, its uncommon. I think, its dangerous too....and you are going to have a hard time with quality control as you will not know who came from who - even IF you get two successful spawns.
Better, try the pair. If they work, good. If not, swap out for a different female/male.
Don't worry about females and their eggs. They will either release and eat them, or reabsorb them. I have only ever caught one female eating eggs.
Good luck! I think they will be similar in requirements to your birds if you get any quantity of spawns. You probably know of the obvious ways to make it easy, like lists and records, routines, database etc. Mine take only about an hour a day total, maybe 2.5 hours on waterchange days.