I scouted Craigslist and joined multiple Facebook local gardening groups for freebie pots. Eventually, a woman approx 1 mile from my home had over 200 trade gallon (approx. 3 litre) plastic pots AND their carriers free to a good home. I snagged 110 of those and about 80 pint sizers with their own carriers for other grow projects. Price: zero, add a little for the gas to drive over there to pick up the stuff. And the water, soap and bleach to clean and sterilize them...
Other expenses for starting approx 180 cuttings and up-potting twice (from starting in moss in ziploc bags in shoeboxes inside of humidity bins, to 24 oz. cups with grow media, to gallon-size plastic pots):
2 totes/humidity bins from Costco at about $7 each; 12 plastic shoeboxes with lids at $.99 each; four or five "bales" of the good orchid sphagnum Moss at about $5 each; four or five sleeves of 25 each 24 oz. clear plastic Smart&Final cups at I think about $7 each; two sleeves of opaque blue plastic 24 oz. cups, also $6 or $7 each; 1massive Bale (over 60 lbs) of ProMix HP soiless potting mix, about $55 with tax; 3 each smallish bags of perlite and vermiculite, $5 or $7 each. I also laid in some very fine fertilizer (Organicare Pure, something like $25) for sbout 20 lbs--should last a couple years), some cheap fish emulsion stuff (something like $9/gallon), another Organicare product called Silicon Blast ($20) to help roots with hot weather as I move the starts outdoors here in Phoenix, AZ. Some ancillary expense for tree labels, Ziploc bags, a bottle of household bleach, a couple new spray bottles. All in: looks like something close to $285 maybe $300, NOT including the cost of the cuttings themselves which if I remember was also something like $300 or $400. That latter figure was to go from 1 in-ground fig tree, to buying an additional 3 West coast-grown whips, and an additional approx 50 varieties of either treelet starts or about 180 cuttings. Obviously, a more sane person might start with just a few varieties, but I had the time and the "focus," so... Point is, this coulda been much less costly if I had gone a little slower
But a lot of this stuff is a one-time investment; I recycle even those plastic cups that I don't have to cut up to free very insistent roots before up-potting to the gallon containers. If I still have the mania next year, I would only have to refresh my inventory of potting media, and look for new gallon (or whatever size) plastic pots
Those were my economics to put through about 70% of the 131 cuttings I've started so far, the balance having failed at one stage or another. Still have about 50 to start