This post is a little train of though, so bear with me.
First up, there are the cost savings to consider. From what I’ve figured out, there is an initial investment (I’ve been ebaying):
Film Retriever/Cap Remover£5
To me that looks like about £40 to get started for basic film development - say black and white. If you want to head into the heady and temperature sensitive world of colour film development, you’ll need someway of maintaining temperature. Another post for another day, when I’ve built my Clive’s-Über-Awesome-Self-Electrocuting-Water-Bath.
So lets say £40 to get started - but you’ll also need chemicals. This is where my math gets a bit unmathematical.
Let us say you’re developing 1 x 35mm film in a Paterson 4 System tank, you’ll need 400ml of finished/diluted chemical, per process. I’ll try and price that now.