Probably the cheapest way to do C-41 is to use the Dignan NCF-41 divided color negative developer. There was an article in Darkroom & Creative Camera Techniques Nov/Dec 1995. Works like a traditional two bath developer.

Bath A

Water 400 ml
Sodium bisulfite 0.5 g
CD-4 5.5 g
Sodium sulfite (anhy) 4.5 g
Water to make 500 ml

pH @ 24C = 6.5

Bath B

Water 800 ml
Potassium carbonate (anhy) 53.0 g
Potassium bromide 0.5 g
Benzotriazole, 0.2% 1.0 ml
Water to make 1.0 l

pH @ 24C = 11.8

3 minutes in each bath at 24 deg +- 0.15 C with continuous agitation.

All remaining processes at 24 deg +- 3 C.

Use Kodak SR-29 bleach 4.5 to 6.5 min then wash 1 min.
Kodak F-34a fixer 4.5 min and wash 4 min.

Stabilizer: 5 ml of formaldehyde plus 1 ml of Photo-Flo in 1 liter of water.

Bath A has a long life but Bath B should be replaced when it gets cruddy.